L. Richards was a maker of antique flintlock firearms, such as their No. 6 pistol. Unfortunately, they are fairly rare, and there is no public records database for MOST antique firearms. Sorry.
Two: Hand guns and Long guns
Only two; hand guns and long guns.
Millions.
Long guns, hand guns, artillery
There are only two types of firearms. Long guns and hand guns.
Strum Ruger made many 22 caliber hand guns. It would help if you Identified the model
Hand weapons and crew served.
There are only two types, long guns and hand guns.
Guns come in many different varieties; among them are pistols, rifles, handguns, and shotguns.
A lot
No way to know.
10 million + worldwide