I would call Grainger.
I've bought just the 12V motors for my Pellet Stove for 1/2 the cost of OEM. Just the motor, had to put it in the existing housing.
Do you have a local community college or High School tech college? Might be able to find an electrical class that could trouble shoot and repair for parts. Just a thought.
One other thing. How old is it? Does the awning/motor have it's own warranty? Some components like heaters and stuff have their own manufacturer warranties that are longer than the warranty on the whole RV.