Spotted this link on the advertisers at the bottom of the page, looks like they have any gear ratio you would want for an 8" rear, prices look reasonable, too....http://www.drivetraindepot.com/store_axle2.asp?axle=57
The site also has a neat gear/tire size calcalator you can see the difference a taller or shorter tire will make, different rpms for different gears, rpm at cruising speed and other things. It's mainly a 4wd site, but the info is priceless.
Here's another site http://jawsgear.net/store/catalog/Good to compare prices with. Don't know anything about either of these companies, just thought the info might be helpful.......
Man...hahaha I've broken a 3.00, a 4.11, and a 4.62 geared carrier...time for a 9 inch I guess heehee