Unfortunately it's not the parts that are expensive, it's the labor. If you are getting a 35mm SLR repaired in the USA it'll probably be a minimum of $75, and possibly more.
I absolutely love K-1000s, but I have to admit, it's probable that it would actually be cheaper to replace it with another used K-1000 than repair it. On the other hand your lens is still good. Look for a K-1000 body without the lens or one with a different lens than you already have. I see K-1000s with an f/2 50mm lens all over the place for $75 to $125. Keep your eyes peeled and you can probably find an even better deal.