Did colt make the butler pistols?
These are modern firearms , made during the 1970's. Colt
reintroduced their Number 3 derringer in .22 Short in 1959. These
were made on and off by Butler for Colt until 1978, In 1978 Colt
dropped the derringer and Butler then sold these derringers under
their own name until 1980. They were sold singularly and as sets
such as " Lord and Lady". The bad news , they were made of very
soft Zinc alloy without even a barrel liner. Even shooting the .22
Short will strip the rifling in a very shot period of time, so they
are not even shootable "fun" guns. Really for display only. Value,
in the condition you described, maybe a hundred dollars maybe
less.