I've had mine for over 15 years and it is still my primary camera. During all these years, I've taken it to service only once, for cleaning after shooting off-road mud rallies in the rain. I have a Pentax MV-1 as a backup, a Sony Digital, a Yashica MAT 124G medium Format, and now I'm thinking about an AF system. But the K-1000 will ALWAYS be my best and most trusted camera.
So, yes, keep it. Or I can take good care of it....
I love this camera. It's truly a workhorse camera. This was my first SLR given to me by my father. I still have it. Unfortunately I loaned it to someone and they put alcohol on the lens to remove what they thought was a hair. They took off the emulsion and now everytime I look through the viewfinder, it looks like someone took a big black marker to it. :x My cousin who is a pro photographer says it is too expensive to replace. I still love the camera though. Definitely keep it.
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.