What should I offer for S/42 1939 luger (UPDATED)

[MilitaryTorch]

Originally Posted by Mike Z

Steve, To Me Personally A mis match mag no way makes a shooter. Aftermarket grips really hurt it.
Mike Z.

Mike the seller has another 1940 S/42 luger that is all matching in 90% condition with a mismatched mag.

For the argument sake if all matching value was $2000 how much would you discount the mismatched mag?

Thanks a lot