I like pre-war Merkel o/u engraved shotguns, . . . .
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A friend took in a Luger and wanted to swap it for my 520. I said no way. Another friend bought it and wound up selling it to a Chicago area dealer for twelve hundred, and that guy had bought it for resale... I could have had it for 350, which is what I had in the 520. Mauser Banner Luger, original holster and two matching mags, exc. Cond , no idea what that's worth today.
For me it was this Russell Smith engraved 29-2, not cheap but you only live once.