Go to the muzzleloadingforum.com
There is a sub-forum which deals exclusively with firearms identification.
You might have to sign up up and become a member to use that forum. However, post your pictures there and if the folks there are unable to I.D. your handgun I'm sure they can point you in the right direction for more assistance.
You might also post pictures here, just never know who might have info you need. Good Luck.
RJ