There have been a few guys making and selling a range box out of a 1350 so you could have dual cases but they have stopped making them for one reason or another.
These cases are the red headed stepchild of the off road world, no one makes adapters and there's no aftermarket support (these cases are chain driven so you can't swap out gears).
The only real aftermarket option is an Atlas II case which is built to your specs and more importantly built with the 5 bolt pattern and 25 spline input to bolt up to your stock trans.
Advance adapters also has an adapter to bolt up a 700R4 which really opens up your options for T-cases.
Quite a few people have built their own "doublers" using a 1350 and a 1354 case. Search around on rrorc.com and rangerstation.com.
