Good electric motors are serviceable. Sounds like that repair shop didn't want to be bothered with the job. That said the shops that used to be near me have long since closed up.
I saved the explosion proof motor on the tube axial exhaust fan 4 times over the last 20 years or so. First it was a centrifugal contact, simple solder fix. 2nd it was a shaft bearing, standard ball bearing. Then I replaced the two capacitors two different times. All the parts can be found at Grainger or McMaster-Carr.
When the capacitors went the motor would hum and not start but if you pushed the pulley by hand it would run. I'm no electrical expert but the motor frame was $800 for the explosion proof and about $400 for non explosion model at the time, probably more now.