I recently got a SIG-Sauer P220 .45 ACP with a nickel slide. From what the previous owner told me was that this gun was made in W. Germany and is kinda a collective and somewhat rare. By the Serial number above the trigger, it was the number with a very small "z" and some sort of symbol beside the z. I was wanting to know if any of you guys had any info on this gun. it would be greatly appreciated!!