yes, casters have weight ratings so if they say they'll support 50lbs, then 4 x 50 = 200lbs total, and so on. be careful when adding casters to any machine, it can make it quite "tippy", ( by placing the machine up on casters you are raising its center of gravity) so put then as far out on the corners as possible. a fairly square-based machine like a Vendo V63 isn't as big as a concern as say a more rectangular shaped based machine.
Would a Vendorlator VF-165 be a good machine to put these on? It is 64" tall, 32" wide, and 23 3/8" deep. It does seem to be rectangular.