I took the transistor out for testing and removed it from the heat sink before testing. Your website was handy and I found a BD239C om mouser as a replacement.
I recently purchased a Vector Research VR-5000 Receiver off e-Bay. I bought it for sentimental reasons since I had one in college. If I totally screw it up I did not ruin a classic Pioneer/ Sansui/ etc...
I am pretty new to vintage equipment and have very modest electronics skills.
Here...