I don't know how beefy a set-up you are looking for but i opted to do an Explorer 8.8" posi swap into my '71 Ventura. I chose 3.73 gears and gained 31 spline axles, rear discs and better emergency brakes than stock. The width is almost perfect(1/8" narrower from wheel flange to wheel flange) and they are much tougher than a 10 bolt. in fact,I'm told that they're comparable to a 12bolt in strength.I'm having absolutely no luck here on the West coast trying to find a 8.5 10 bolt rear end for my 1968 Acadian (on a budget).
I've called all the local junkyards, and checked the usual Craigslist, Kijiji, etc.
Where are you guys having the most luck finding parts. Does anyone know a great JY out West or are you just biting the bullet and buying out of the US?
I really want to upgrade to an 8.5 over the winter
It does require some fab work,and re-drilling the axles and discs for chevy bolt pattern,but it's not a tough job overall.
Food for thought.....