Ok forgive me if this is a stupid question but I haven't been able to find information on this anywhere.

I may be buying a WASR 10 from a friend. He is not the original owner so he doesn't really know the history of the gun. His accepts double-stacked mags. From what I've read the WASR 10 originally came with single stacked mags. Wikipedia shows the doublestack listed as "GP WASR 10". His is marked WASR 10.

My question is: Are GP WASR 10's marked "WASR 10" or "GP WASR 10" is there any way to tell the difference between the two? My only concern is that his may have been opened up to accept double stack and may not meet 922r