Sizing Elevator Motor based on HP only!!

[Cartoon1]

I have a 15HP elevator motor at 120/240 3 phase. I have no FLA or any kind of amperage from the manufacturer whatsoever so far, they keep pushing back. I plan on using 430.250 to get the amperage and multiping it by 250% from table 430.52 for the circuit breaker size. And for the wire size i plan to use the amperage from 430.250 and multiplying by 125% . Is this way sufficent enough to size the elevator motor? Or is there a different way?? thank you