Thought about buying the reamer kit myself, once upon a time. Yes, cost-prohibitive for an item you'd use a couple of times.
I haven't worried so much about the cylinders as the forcing comes; some of the factory cones are garbage. A little reaming would clean em up and make em much easier to clean... may even help the accuracy. Again, haven't shelled out the $$ for something that will collect a lot of dust. Now, I do have several .45s (well, I did be fore the accident ) and may get a good bit of use initially, but then... dust.
And to answer your question; no, I have no idea who can do the reaming.