Again their are rare models, some of the mustard stoves demand attention, some of the zinc stuff, any of the WWII goods, Forest Service stuff, etc.. but even then they going rate is $50 for a stove someone just put $30 worth of parts into 
<------ This guy has a few dozen Coleman appliances from the 40's-70's.
What do you have? The reality is Coleman stuff is very neat, very collectible, but very low priced. You can't walk into a DI without finding a 60's or 70's 2B or 3B stove. Lanterns are a little harder to find particularly with the globe in place but you an find all of the OE resto places from online retailers or Vic's in SLC. Heaters, one burners, etc are rarer finds but again I've never paid more than $10-15 for a Coleman, going rate is usually like a IH Scout, "get it out of my garage"
, its marginal. 
The older stuff is built to last--you just can't beat the quality for the price.
I'd skip eBay and watch the thrift stores, again you'll pay more in shipping than I have paid for any of my coolers. As far as practical use, they are far more robust than a current generation cooler but they do not insulate nearly as well, particularly when compared to a Coleman Extreme or similar. I rarely use my Coleman coolers as a cooler rather as a dry food box as they have far more interior space compared to a modern cooler with similar sized exterior. I use it once a year as a true cooler (Relic Run when the fridge is not allowed
If your truly looking for a cooler that strikes a better alignment of quality and practicality, options exist. Engel, Yeti, etc however they are hundreds of dollars and often designed for larger applications.
http://www.coleman.com/coleman/Cole...egoryID=8581&gclid=CN7wjtnzwqgCFQkCbAodXHzUrA
Mine (50 qts), with 5 lbs of dry ice in the bottom, will keep a 8 lb homemade block of regular ice (denser than the blocks from the store) frozen solid for about 3 days, then it thaws slowly for another 2 days.Supposed to keep ice frozen for 5 days at 90*F. But you could just read yourself
