I used a Tbird rear rim. Its 16 inch and forty spokes. I got it off of ebay for $75. You can also check Triumphrat.net There is classified section for the T-birds.
They are the exact same hub as the BA uses. I used the stock tbird hub and spokes and bought a 5.5 inch wide Excel rim from Buchanan($350). You'll need to go 5.5 because a 200 series tire won't work on a 3.5 inch rim. You can take the hub and rim to your dealer they will lace it up for you. If you want to stay with the stock 15 inch rear wheel, you need a 15 inch rim and spokes from buchanan. You will spend at least $500 for a new rim setup not including the tire. Let me know when you start if you have any questions. I've been through it and I'd be glad to help you through it too.
Fryguy.
