With that amount of power I would look into a 12Bolt or 9 inch. But if you do just want to beef up the stock 10bolt, I would get a Torsen, and use an aluminum support cover.
I got my Torsen used off eBay for $150.00 and it showed very little wear.
You can get a new Torsen (TrueTrac) from here;
http://www.ringpinion.biz/product_in...de5117d8451d3d
or you can contact Moser and see if you could get one from them. Moser does not list one for the 7.5-7.625 10Bolt on their website, but they are a vendor of the TrueTrac so they may be able to get you one.
http://www.moserengineering.com/index.html