Hello Barr,
Are you sure the serial numbers are wrong? What numbers are on the barrel? Not 8,82, 8,83 or something like that? Some barrels were marked with the serial and some were not.
You never know about Luger's, sometimes they shoot lousy even all matching, and some mismatched ones shoot like a charm. But of course, a matching one is more likely to have its original tolerances not messed up !
If you look on the gun auction sites, Artillery Prices, even "shooter" ones are expensive, more than $800.