Kirby
You can have some rebuilds done through some Kirby service centers with various results. They can always get wheels, bags, cords, brushrolls, belts, etc. and do some polishing.
However, you can get a superb rebuild done through the Kirby Company in Cleveland, OH. They have a separate address and facility where the rebuilds are done. If you are the original owner and have the owner's manual that goes with your vacuum, you remove the handle, (unless you want it buffed too), and pack it up and send it to them. The rebuild fee is published in the back of the owner's manual. Depending on what model you own will depend on the price. The age of the vacuum is a factor.
A model 510 from 1950-51, can be rebuilt for $12.50, whereas a model Classic III from 1976-79, can be rebuilt for $47.50. The price does not including shipping in either direction. Another thing to keep in mind is that Kirby NO longer has the original colored trim, wheels or bags for models before the model 562. Sooooo, if you send off a 561, let's say, it will come back with tan trim, cord, wheels, bag, bag topper, and bag guard thus making it not totally correct for the purist but still a wonderfully rebuilt vacuum. This why we see so many "mix and match" on ebay and at vacuum stores.
If you do not have the original owner's manual, (they request you send a photocopy of the last page with the model, serial number, dealer's name and date purchased), there are ways to get around that too.
I see in your profile that you are a young man so you may want to have one of your parents help you with this. No disrespect intended but minors can't enter into a business contract and you would indeed be contracting with Kirby to do a rebuild if you chose this avenue.
I hope this makes sense and please feel free to email with any questions. Fred and I have sent many vacuums to Kirby for rebuilds and can help you with this is you would like. I am getting ready to send in a 510 and Classic III to be rebuilt by them. The great thing about having Kirby do it is that all origianl factory specifications are met and all genuine Kirby parts are used as opposed to "bojack", meaning replacement but not original nor genuine. Plus, the polishing they do is fantastic!! I done a lot of hand buffing and even using different polishing compounds and power buffers, you never get the shine that the Kirby factory puts on them!
Hope this helps!