Hi,
Actually, IMO, the other carving on the "Lion" Beck is more difficult than the lion. If you can draw it well, make sure the background is cleaned up well, and can cut clean incised lines, I don't think the lion is particularly difficult. There is very little relief sculpting and Beck achieved some 3-D effect by cutting incised lines as you would shade an engraving. There is a version of this gun by Homer Dangler in Robert Weil's book "Contemporary Makers of Muzzle Loading Firearms".
dave