I have just been down this route with these engines.
It's worth R32000 which is what the imported Jap ones go for and there is stock of both M88 and S38 in SA now for that price with warranty.
I know it's a little less than you expected but imports are driving prices down a little as these engines are more common overseas than here.
Throw it on the Gum at R50K see what happens, you might get a sale.