Alain Lamothe (caporal30 here) has a real nice blog called Vintage Chainsaw Collection.
http://vintagechainsawcollection.blogspot.com/
"A CHAINSAW VALUE ???THE BIG QUESTION!!!!!!!!!
Chainsaw value...This is the big question no collector's want to answer since there is no real answer. Many factors can influence the price of a saw such as the overall mechanical condition of the saw, the quality of the paint and decals, the saw is a runner or can only be used for parts, parts are missing or broken to name only a few.
You cannot put a price tag on a chainsaw and if you intend to sell one dont think that you are sitting on a gold mine...........
In a collector's point of view what is the saw worth for you??? You need to figure out what it is worth to you. As a collector, i cant know that............. This could be influenced by a sentimental value, a saw that was own by a relative or selling it for a friend and more.....Only a transaction that will make both parties happy will occur if you have an idea of what you want for your saw............. otherwise it is just like buying anything. If you have a price in mind to sell a saw.........tell the buyer your asking price and only then you will find who might have an interrest and the saw may sell."
Alain"s site has a lot of great pics and history of the old saws, including Mercury / Kiekhaefer and Disston. Scroll about half-way down and in the right hand column you will see some tabs you can click on for more info. You can easily spend hours looking at everything he has posted. I do highly recommend his blog if you are in anyway into older saws and the history behind them.