I have bought a couple of decent (and this one is far better than decent) for $1000 and re-sold the Krieghoff mag for a profit - they are worth more than 'normal mags'...
I was at a gun show in Chantilly, almost across from Geo's table was a guy with a barely decent WW1 luger. I looked at it and it had a Krieghoff (eagle 2) mag in it. Asked if I could buy it, he said, no, I should leave it with the gun, thats how it came. I said I understood, but a wood base would be correct. I said, I would trade you a wood based mag and $100 for yours. he looked at me like I was an idiot. I walked over to my table, grabbed a wood mag and traded him...
I would not say that I made a huge profit when I sold it, but a small profit and got an ok kreighoff back into collectors hands
Ed