need th400 trans for 80 gmc 3/4 ton 4x4

[xcaret]

I have a light duty 400 trans in my 80 gmc 3/4 ton pick up 4x4 that now has a cracked converter housing ,and probably a cracked flexplate..I'm looking for a heavy duty ( has 6 bolts holding the torque inspection cover on ) or even a light duty 400 trans that I can use the case to put my good parts from mine into ..so I just need a core.
Any one have one ?? I'm in calgary ..my email is [email protected]