Spraggs seem to fail unexpectedly for reasons unknown to me. The replacement bolt-in spragg is very reliable. Real tranny pros may have recommendations as to specific clutch/band material. Always replace the convertor. You can do it.
The bolt in sprag is the same as the sprag that is in the trans already...10 roller with springs......
If the cam and retainer are damage...you just drill the pins out and replace it with a cam and retainer that has screws...no different...takes the same 10 rollers and springs..
Just buy a new spring and roller kit.....for 5 bucks off ebay....
The sprag did not change until the 1988 models.....then the one piece caged sprag was used...otherwise they are all the same...