HoH: The S/N format you describe is the PW Arms marking from recent (within the past two years) imports. I believe the S/N's are now well into the mid 20's if not 30k's. What arsenal and year code did you wind up with? Seems like they are pretty much all Jianshe /26\ arsenal guns with year codes mostly from 11, 12, 13, and even a few 14's thrown in there.
Year 10's were quite heavily represented early on in different import batches (IArms, Foxtrot Lima, etc.)