This is a rare Mauser Large Ring C-96 Broom handle pistol. According to the serial number 31058 it was made in 1902. 7.63 Mauser caliber with a 5 ½” barrel. It is a relic of another time.  70% of original finish. Just the pistol is available. Import marks are from VON LENGERKE A. DETMOLD New -York. Manufacturer. Currently semi taken apart to show all matching numbers.  Your going to have to reassemble before it is working order.  I have shot this.   Should be checked by armsmith.  Prove to be you can own guns and are a NH resident or we go to a FFL and Split the transfer fee. These are usually expensive items. Shipping $75 via my FFL to your FFL for out of New Hampshire to state that allows this gun.