I talked to this guy's GF and here is her email to me today:

Hi Candace,
I spoke with G___ last night and he doesn't want George to go to the vet. He is adamant about this, but did say that if it looks like George is getting worse he will consider it. I know Garry well enough that it is no use trying to convince him if his mind is made up.
In the meantime, i will buy some of the tartar control treats you mentioned before (greenies). George is actually doing better than he was 6 months ago - eating well and able to climb stairs more easily. I do appreciate your concern, and will talk to Garry again if George's health appears to be worsening.
I replied and thanked her twice for trying):

The best price for Greenies I have seen at Zellers - but Pet Planet here in town is pretty good too (over near Shoppers). If you are in a pet store, ask about drops that are added to water to help tartar. There are several about. Lastly - I hear that filtered water is really great for bladder and for teeth. There is a Brita pitcher at the 2nd hand store for $8.00 and President's Choice filters work great as well as being cheaper than Brita! :-)

Also - pet medical research used to think that kidney cats needed LOW protein diets. Apparently that is not the case, as long as the food is high-quality protein. Two Canadian brands I have used are Origen and Now (the latter has an umlaut over the o). Pet stores often have samples. If George likes it (it can have warm water on it so George can eat it), that may help put a bit of weight on him. "Now" may also come in a wet formula. These products have no grains in them, which is why they are high in protein. Wellness and Natura have grain free wet...and these foods, wet and dry, will have other vitamins in them.

No food at a vet's is grain-free, and my vet totally approves of my using grain-free food with my guys. They do well on it - TOO well! lol - and this food also changes the pH of their urine so crystals can't form.
So...that's all we can do for now. I hope drops in the water (and George drinks lots) might help loosen or dissolve the tartar over time...cause that's the only option. George LOVES treats, so Greenies and maybe some Medi-Treats will help remove tartar as they are hard treats).

Thanks for all your prayers and thoughts. Keep a few coming, ok?