send the pics to a friend in czechia who collect old bohemian made guns because it falls into his area. he write me back that he was the second bidder on this years ago and be happy it still exist but it dont become cheaper over the time - quite the opposite

the design is typical for old german airguns and also came into the united states by german gunmakers. before the great war they were made most notably by Oskar Will Venuswaffenwerk in Zella St. Blasii, since 1919 connected with Mehlis into Zella Mehlis near Suhl
here is typical Kurbelspanner https://forum.vintageairgunsgallery.com/spring-piston-crank-wound-airguns/o-will-kurbelspanner/

the design was later simplified by adding a lever like this one

https://egun.de/market/item.php?id=8223315#

from time to time I get lust to by such a airgun