M/49
I'll be of no help this time around.
I haven't seen any M/49s for sale anywhere since about a year and a half ago. They had a bunch hit the country then, and were selling them for about $900.
These were well-used military guns, but still pretty darned good.
A guy named Michael Yin (in CA.) ran a website called the Eastern Cannon; he probably knows as much about the P-210 and M/49 as anyone around. But his web site seems to be down, or out of business. I did a search a few minutes ago and nothing came up. You might try a couple of the various SIG forums, to see what they can tell you. Someone there will know a lot about P-210s and the M/49.
I've got a P-210-6 (basic gun with match-grade trigger). From what I read and heard about the M/49s, y ou might be better off saving a bit longer and getting a use P-210. One of the problems with the M/49 is that some have alloy frames, which wear differently than the steel framed P-210, and some have relatively worn barrels; a replacement barrel must come from SIG, and they're about $800... It may be a false economy to buy one that's not absolutely in top-notch shape.
(Mine is now for sale, on consignment, at my local gun shop. I'm buying a new truck and want to reduce my debt. Its like new, with 2 factory and 3 after-market mags. Original box, proof target, al papers, etc. I'll probably throw in a good holster, too. I'm offering it for $1550. New versions of my P-210-6 are going for over $2000; I got mine for about $1400, and bought the extra mags. I'm actually going to take a small loss. You should be able to find a used one for that amount or less. As I said in some of my earlier messages, I shoot a lot of IDPA -- that's my main shooting interest, nowadays -- the the P-210 just doesn't cut it for that game.)
Still a great gun, though.