Please help rear brake calipers

I have a 97 gt 5 speed that I was trying to bleed the brakes on and when I opened the rear passenger bleeder screw no fluid came out so I took the screw completely out to try to see the problem and the threads are completely rusted off the screw and the clippers is stopped up with rust so I know I have to replace it my question is I have no money at all and need my car I have a complete rear end from a 97 5.0 mountaineer I'm wondering if I can use the calipers from it until I can afford new ones I know the e brake won't work but it doesn't work anyways
 
I did a quick cross check of part numbers and looked at the pictures on Rock Auto...I'll say "no". Recommend you go to your local parts house and do the same thing. Also, why not do a visual comparison of the parts you have in hand?
 
No, they are not compatible. The mustang rear calipers are unique to that vehicle only, so you will need to source a caliper off any 94-04 Mustang. The caliper portion, with the piston is the same on the rear of all mustangs, so you can take a trip to a boneyard and try and grab one.

Otherwise, cheapest caliper I see for sale is a $48 reman from autozone plus core.