Build a 904 or buy one off the shelf?

If you don't want to rebuild it yourself. Find Butch in Hemet to rebuild it. Good guy and reasonable. You'll have to take it to him. I have his number somewhere around here.

Check simple stuff first.

You forgot to ask him if the linkage is hooked up. :D
And if it is, you forgot to tell him the clearances are way too big and it needs a rebuild, or the front band adjustment is too loose.
You also forgot to tell him that it's a possibility that it could be low on fluid and foaming, or might have a plugged up filter, or ask if it buzzes in gear.

Ya slippin there Rob? :D