Ya'all have way too much time on your hands.
Fifty years ago my wood shop teacher, grandfather and all my uncles believed a stockman had always been any manufacturer's knife that had a master clip blade and secondary spey and sheep's foot blades pivoting on opposite ends. To simplify this discussion lets suppose they were correct. Would that make it stockmen?
Depends on whether you are referring to the possessive case or to multiple revolvers??
Here is the rule I like:
If the word ends in a vowel (a,e,i,o,u) + y then just add s.
boy/boys, journey/journeys, key/keys, tray/trays.
If the word ends in a consonant + y then y changes to -ies
country/countries, baby/babies, body/bodies, memory/memories, sky/skies, variety / varieties...
Please note that you don't use spelling rules with proper names just make sure you use a capital letter.