? on Savage No4 Mk1.

I have a Savage made Enfield That has been pretty well worn. Got it from my nephew who got it at local show.The bolt is not Savage but the rest of the parts minus the barrell are. Barrell has no markings of any kind.My question is what do I have? The serial number is
82C2104 on the reciever by the buttstock. Underneath where the serial number is there is no date just the LB logo that LongBranch uses. What is it and when was it made. I would also like to get a Savage bolt body an cocking piece to relace the ones I have. Thanks, Mike.:)

You have a late made Savage. The later ones were not dated. The mark is a plain "B" it shows up on Savage made no. 4s fairly often.