I thought you were in Palm Springs.
Spend a weekend in Los Angeles and Orange and San Diego counties.
Even now, those places are loaded with excellent condition W126 cars, low mileage, garaged, low priced examples of beautiful ones.
The reason, as you know it it is the center of US car culture, and the weather is very kind -- which means no salt or rust issues, and the fact that there are SO MANY there, it drives the prices down.
WAAAY down.
Not to mention that many of them are well loved, carefully maintained. Plus there is a plethora of shops and places to cater to and take care of them, and they do well.
It should be real easy and fun.
Check Craigslist, private car lots, auto trader, cars.com, even BIN on ebay or local shopper newspapers.
NOW, the best ones show up for sale, though, country wide on the internet forums that talk about them, google benzworld w126 for the best ones.
For the w126 See also the that I wrote back in 1998. For the sedans, just add two more doors to this guide.
Prices not accurate now, since I did not update, but it has been well received over the years.
http://www.mbcoupes.com/buyersguide/buyersguide.htm