Hello Cap'n, and welcome to the board. Christophe Funk is a well known German maker, but like nearly all German makers there aren't any records left. There was an article on Funk in an issue of "Double Gun Journal" some time ago, perhaps a call to the publishers might pinpoint the specific one. While the serial number is unlikely to be very helpful, it's possible that the other marks on the underside of the barrels will tell quite a bit about its dimensions and proof date. If you could post pictures it would really help, or at least describe the various marks and numbers and we'll see what we can come up with.
