Which city are you in? if you are in Toronto, you may find a lot of W126s and W124s, when I was looking for a Mercedes in this August, I took a week vacation and drove to Toronto 3 times, visited a dozen of dealers, I have seen quite a few W126s in excellent condition, no rust at all, they all had service records from day one, I guess they have never been driven in winter, and they are reasonably priced, below Cdn 12K.
My W124 92 400E is also in excellent condition, the body shows no rust at all, despite it has 200K km on it and it has been winter driven.
I am in Ottawa, it's such a small city, I tried about 3 month couldn't find one locally, they were selling a beat-up 1987 560 SEL for Cdn 15K here, I know in Toronto I can buy one in excellent condition for 5K less.
Be patient, you can find a good one even in salty Canada.
99 BMW 540i 6-speed 110K Km
03 SAAB 9-5 wagon 80K Km
92 400E (Sold) 245K km
Still missing the days with the Benz, it kept me busy.