Does anyone know of a dealer for replacement parts for Pella Windows that would be less expensive than buying directly from Pella? Buying replacement "clockspring balance boxes" from Pella for six windows would cost over $800. The windows are 37 years old (from 1968)-- original Pella, double-hung windows. My dad can do the work himself; he is just having a hard time finding a source for the parts. Also, are there "generic" parts that could be used instead of official Pella parts or would that not be recommended? Any help you can provide would be great. Thank you.

Cindy