3N standard means it has a standard or small arbor as opposed to the large arbor. This will allow it to hold more backing. However, a Super 3N is designed for 3 or 4-wt rods.
Abel previously offered a "Big Game" series with a different numbering system a few years ago, but now offers the "Super Series," which is available in large or standard arbor configurations.
For what you will be targeting, a Super 8 would be ideal. The new ones are sold as a 7-8N, which is designed to go with a 7,8, or 9-wt rod. However, you can still find Super 7's, 8's and 9's brand new on auction sites for less than a new 7-8N.
A Super 8 with large arbor will hold a 8-wt line with about 200 yards of 20-lb. Dacron backing.
Try this link for information about current offerings and backing capacity:
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