Phosphate bcd4 bring back

Last week I was able to buy this rifle from my former boss (gun shop owner) I had worked at this gun shop a few years ago, I took this rifle in from a guy who had found it in the attic of a house he was flipping.
A very dry and dusty duffle cut bcd4 5 digit serial # phosphate finish on most parts (bolt,shroud,barrel,floor plate, front band) perfect bore, all matching numbers except....... the stock appears to be a byf44. With 5 digit serial number in barrel channel. My only explanation is the soldier brought back at least 2 rifles, and reassembled them back at home not caring which stock went each rifle.......any other explanations, ideas, thoughts on why a duffle cut late war bring back wouldn’t have correct stock and/or ball park value