I know you Merkur people (and others likely) like to drop in those supra diffs, and there's two for sale (not mine) in the midwest right now:
$100 - LSD, should be 3.91 ratio (89.5 turbo car)
http://milwaukee.craigslist.org/pts/5755446660.html
$150 - LSD, 3.73 ratio
http://rockford.craigslist.org/pts/5717458498.html
I may pick up one if I'm nearby but figured others may be looking as well. Cheers.