if you're looking to buy a blower, i used this exact blower for 5 years. it worked flawlessly for my 4' evaporator but i sold it with my evaporator a few weeks ago. had it hooked up to a 3" duct pipe into the arch. 3 speeds, think the highest is about 300-325 cfm.
https://www.amazon.com/STANLEY-65570...6&sr=8-1-fkmr0