Hey Matt, you should have a ball with that outfit in the salt-- a 9 weight is a great choice for inshore saltwater.
The Okuma SLV should be fine for chasing reds, specs and spanish macs, bluefish and flounder and all kinds of other stuff in saltwater. Where it might run into some trouble is if you were chasing fish that can really smoke like small tuna, jacks, bonefish, permit and or bigger stuff like 100lb sharks etc.
But for reds and that kind of stuff it should be fine. Just give it a good rinse in freshwater after each use and back off on the drag so you don't compress the cork washers. As with any reel used in saltwater, sand can be deadly so what ever you do, don't lay it down in the sand to land a fish or to take pictures etc. which is common sense-- but you also want to keep an eye out so you don't dunk it when you're wading in the surf zone where there might be a lot of suspended sand in the water.
Although it's an inexpensive reel, it should hold up reasonable well with just a little care like freshwater after use and occasional lubrication to the cork drag each season - hopefully there should be some instructions with the reel.
As for your fly line, I'd definitely try it out in salt-- the main issue with some lines is their ability to retain a certain amount of stiffness so they don't collapse in the face of wind-- which tends to be a much bigger issue for fly fishing in the salt. Good casting mechanics are the biggest asset of course, but sometimes having a stiffer line can be a big help. Fly lines can be expensive so definitely try the one you have before buying another just for the salt. If you do buy another line at some point, it doesn't have to be a redfish line-- try a few different ones with your rod before you buy if you can, including "saltwater" and "bonefish" tapers.
As for a leader and tippets, although you can buy pre-made ones (from Rio and others) at $4.95 a pop, this gets expensive and you can easily make your own.
Saltwater leaders are generally pretty simple. In the case of leaders used with sinking fly lines they can be just a short 3-4' usection of straight (no taper) 16-20lb mono.
For the longer leaders used with a floating line, a heavy butt section will help them turn over at the end of the cast and prevent your fly from landing in a tangled heap of limp mono at the end of your fly line. Assuming you're not going to get involved with wire or heavy mono bite tippets yet (used for the last 6" near the fly for toothy fish), and not chasing world records (where you'd want to build leaders using more complicated knots like "slim beauties" and "bimini twists") here's how to build your own simple leaders...
You can use regular Ande mono fishing line- no need for expensive fluoro or fly fishing tippet. If you don't have spools of fishing line lying around, look for a bait and tackle store that spools spinning and baitcasting reels for customers-- you can buy a few yards of heavy 40 or 50 lb regular mono like Ande (not "hard" mono or fluoro) to use as heavy butt material, some 20lb Ande for a mid section, and a 100 yd spool of regular Ande 15 or 16 lb mono to use as tippet.
To build a leader for a floating fly line, use something like 50-60% of length of the total leader as the butt section, then 20% of total length for the mid section and 20% tippet formula. It doesn't have to be exact, just eyeball it-- but you should end up with a leader that unrolls easily at the end of the cast. In fact if you're using relatively short leader, like 8 feet or so, you can just use 60% butt or 5 feet of butt and 40% or 3 feet tippet. For longer leaders you might want a midsection.
As an example, for a 10' leader for spooky fish on your 9 weight, this would look like 6' butt section of 40 or 50 lb test tied directly to the fly line (I use an Albright knot because you can reel it through the tip top and other guides when you're fighting a fish).
To this, add a short 2' section of 20lb Ande as a mid section blood or double surgeon knotted to a roughly 2' section of 15 or 16lb Ande mono as a "tippet".
To make changing leaders easy on the water, you could tie a small perfection loop in the end of your butt section, and a small perfection loop in the midsection. This way you can just use a loop to loop connection between the butt section (which rarely needs to be changed) and have a bunch of pre-made mid section and tippets in a zip lock that you can quickly loop on.
For a 2 section short leader of butt and tippet:
fly line- Albright knot - heavy 35, 40 or 50 lb mono butt section - perfection loop - perfection loop - 15-16 lb mono as "tippet"
For longer leader using 3 sections
Fly line- albright knot- heavy mono butt section - perfection loop - 20 lb mid section - blood knot or double surgeon's - 15-16lb tippet.
You can use this neat link for animated instructions on different fishing knots: Fishing Knots | How to Tie Fishing Knots | Animated Fishing Knots