Well, here you go a Coleman 550 that I found for $15 with all you see below. I'm not sure it was worth what I paid for it. It had some problems, big problems. Otherwise, according to model number this is the first 550 as it has no 'A' or 'B' in the number. As far as I know the stove has no date stamp anywhere except on the instructions that came with it. One difference to mention right off the bat is the fuel cap isn't the tethered type as on later 550s. I know, there are some of you out there that don't like the 550 series of stoves. That's ok, this isn't my favorite stove but I don't have a disdain for it either. I thought I would post what I have anyway for those that do. The first thing I noticed was the whole side of the stove where the main valve is from the burner to the instructions below there, it appeared to have been on fire. The instructions were singed to a nice little tan, obviously not from a tanning salon. As I got to playing with it, I turned the knob and the whole valve and fuel pickup moved like it was just hand tightened and loose to the tank. As you can see in the photos below, the main valve and fuel pickup looks brand new. I did no clean up of it and found it to be in perfect condition, as in new old stock condition. It probably is new but it sure wouldn't have fixed the stove. The second problem I found was that there was probably decades old layers of carbon deposits that were in the burner bowl (which the seller had attempted to scratch out before selling) and between each of the burner rings. I could not see any hole that would have let flames pass through. When I tore down the stove, I realized that the mixing chamber, the rings and burner bowl are one complete unit and are held together by a flared retainer tube. To get at the rings and clean them thoroughly, my only solution was to drill out the retainer. I managed to drill just enough of the flared tube so the retainer could let go of the stack but be usable when I put the parts back together. That appeared to work. Of course, the rings were stuck together until I could chip away at the deposits and break them loose from each other. I had to brush down each ring until every speck was gone. Tedious to be borne for sure. I think this also acted as a preservative as there was no rust nor was any of the rings worn thin. They were still stiff and strong. If you've never seen the inside of the mixing chamber before, well, it's interesting to see how simple it is. The generator passes through the wall of the main chamber and then through the wall of the air inlet tube, which gets it's air from beneath the burner bowl where there is a hole for that purpose. Once I got things cleaned up, I sandwiched everything back together and found that the chamber screw held things together quite nicely. One of the design items that I thought was interesting was the number of O-rings the main valve has! There are five O-rings that would have potentially needed replacing but since the valve and fuel pickup were new, I didn't have to. If you are refurbing yours, you will probably want to find these O-rings and replace them. Another design item is the main valve spindle is not threaded in! It is merely inserted until flush and then held on with a spring steel clip. I was a bit nervous about removing the clip since I could have busted it off in the process and would have permanently damaged the stove. Whew! I guess the valve has two O-rings, the first to stop fuel from passing, the other as a redundancy measure in case the first fails. But how would you know when the first O-ring failed? Hmmmmm. I installed the Coleman Fuel generator instead of the kerosene generator to keep the stove clean. The kerosene generator is the one on the left in the photo with the notched retaining nut. Ok, ok, I'll try out the kerosene gennie later for you kero-fuel fanatics! There are some other interesting details but I'll let you find them yourselves.