Can I use a Leviton MS302-DS switch as a 3-way switch?
No. That is a Double-Pole, Single-throw (DPST) which switch both hots on a 240 volt load.
For 3-way, you need Single-Pole, Double-Throw (SPDT) switches for 120 volts or Double-Pole, Double-Throw (DPDT) switches for 240 volts.
I have no idea how easily you can find motor-rated DPDT switches. One other solution is to use DP, normally open relay, motor rated, with a 120 volt coil. And power it through standard 3-way switches.