Ben,

You'll find dozens of them looking for "Drillings and Combination Guns" on http://www.gunsinternational.com and searching on other sites such as http://www.gunsamerica.com and http://www.gunbroker.com. You'll see what others are ASKING for guns of varying condition and cartridge configurations, what they will actually sell for (their worth) is something else again. Then there are the auction houses such as James Julia Auctions where one can acquire record of what guns sold for. Having inherited the gun from your grandfather I will assume an increase in the guns value to you (it's importance ... that of the sentimental nature) so if only for insurance purposes I'd suggest you play it on the high side, say $3K. From what I see the barrels seem to have some pitting and the wood has a fair amount of wear such as worn checkering and some handling dents here and there. I also see the top lever is at the left of center (typically a condition of a fair amount of use over time). I can't tell, from what I see, if you have a single or a double Kersten lock up (top lugs), a double indicating a higher end offering thus a nice bonus. A "Bockbuchsflinte" or O/U shotgun rifle combination gun has to be in exceptional condition and with a nice scope to draw $3K or better but again as this gun was your grandfather's it may very well be seen by you as a priceless treasure as I treasure those similar now in my possession. I haven't seen, thus far, any mention of you wanting to shoot the weapon. You may want to have some fun with it. I dont have any experience with the 6.5x 58 Sauer and Son but Im pretty sure Mike (Der Ami) or others can help you out. Acquiring 2 20 ga shot cartridges is not a problem. I have acquired them from POLYWAD - http://www.polywad.com and RST Classic Shotshell Co, Inc. - http://www.rstshells.com when I havent reloaded my own.

Regards,

Mark