Those are pretty poorly made and rarely resell over $100.
..........................................................................................................................
Actually the single barrels (mod. D) sell for $100-$135, the 6" double barrels (mod. DD) go for $150- $199, A (mod. DS) 18" double barrel sold for $295, the 5 shot (mod. MR) go's for as much as $355.... these are current "sold" prices on http://www.gunbroker.com ....Now add $25 to $30 shipping and a $30 to $45 transfer fee at your FFL, and you can see that these little scatter guns have become quite the "collector pieces." These prices reflect NIB or LNIB condition firearms...... Note: Although fairly crude in appearance they are stout little guns, I have owned several, and they serve the purpose they were intended for ...
I just bought one--used but unfired--no box $100. Jack from Northeast Pa
This weapon was manufactured by the maker of the MAC10. I have an over-under derringer by FMJ Ducktown, TN. It is a 22cal under and a 410/colt 45 over. Some infomantion is under LEINAD which is Daniel spelled backward. Also COBRAY. JD
It is whatever the BATF (Bureau of Alcohol, Tobacco, and Firearms) says it is since they do the legal defining of firearms. Since Cobray did the modification for sale, I suggest that you ask them, since they surely vetted the firearm through the BATF before selling it.
Blue Book of Gun Values
Cobray derringers are currently in production and have been made for approximately since 1992 .Cobray is the same company who made the MAC 10 submachine gun in the 80's,They are made in several different configurations including single barrel and double barrel with 45 long colt /.410 shotgun shell ( it can fire either interchangeably ) caliber being the most common but i have owned a 357 mag./38 special version and one with a .22 long rifle upper barrel and a .410 lower barrel value is 100-150 dollars in excellent condition they also make a .410/45LC and a .22 LR pepper-box type revolver and a full size .410 shotgun. This derringer is a formidable close range weapon when used with the 5 ball 00 buck .410 shell ....Bruno
Find a gunsmith.
OK
A thousand or so.
Whatever your willing to pay for it.
100-5000 USD depending on specifics
50-200
Not likely. No sn data in published form.