I have no knowledge of the Beseler but I know you would not be disappointed if you got the Kaiser. Great enlargers and still being made.
I saw a 23CIII-XL with the VC head for about $70 on ebay recently. I picked up a still-in-the-box 23CII-XL locally for about $100. They are nice enlargers with loads of parts available - still made too. Should do 6x9. Carriers can be had on ebay for not too much.
However, I must say that I really want a Kaiser. Someday I'll get one new. They look really nice. Check into it though - it might not print the full 6x9 negative. I thought I read something about that somewhere...
Well, the way I see it the Beseler is probably the wise choice since you are on this side of the Atlantic. They are good machines and will handle negatives up to 6x9 cm. The enlargers are common, and still in production. If you need accessories and/or parts, they are readily available both on the new and used market. Kaiser enlargers look like really good solid machines, but they are not terribly popular or numerous in the US. That alone, would deter me from buying one. I've had too many machines that were not common here, most notably a Renault sedan I once owned, that gave me hell every time I've needed a part or service. The situation for Kaiser enlargers might be different in Canada.
If I really do not find what I want, as the last option, I will put my hand in my pocket and go with a new 23CIII.
So far, I think it is the best strategy. When you are like me, a little bit too enthusiast about something, you loose the focus and you become interested by all kind of stuff that finally are way too much for what I want to do, or stuff that would a lot of money to put back in condition.
So if someone knows something about a 23CII for sale, that can be a good deal, PM me. While that time I will keep my eyes wide open.