The R 11 refers to the Borg Warner over drive unit used mostly on Borg Warner T 85 three speed transmissions. The T 85 is very strong and was the model for Ford's "Rock Crusher" four speed. The R 11 is a heavy duty OD and has 4 planetary gears instead of the the R 10's 3 gears. The T85 R11 combos were used in Studebaker V8s including Hawks and pickups, Lincolns, Ford cars and pickups, and more.
I've never seen one of these before but I'm sure it would work for you if money is not an issue.
http://www.ebay.com/itm/281229301802?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
