i THINK this is correct, i had a -80 gearbox that was the same as later 4 speeds.
if that is the case for yours aswell the saab number is 8728677 for the oi-stick housing.
You will have to buy the 5 speed kit or every part 1 by 1. there is no kit that fits the 4 speed .
What you need is really
* Oil stick cover gasket 8728677
*Primary chain cover gasket 8732380
*Diff cover gasket 8728651
*Input shaft seal (in to primary housing) 8710881
Then there is
*Seal for gear selector rod (requires dissasembly to fit, doesnt usually leak)
*outgoing axles seals. (also usually doesnt fail)