This Field Guide works even if the stove in question has been repainted, is a hopeless rust bucket, or is just missing its decal, as is sometimes the case. It covers the earliest stoves even though they usually still have their riveted metal badges, and goes to the late 40's, after which the U.S. stoves all had some sort of permanent marking, usually either an embossed or stamped model number.
The basis of the identification key is the stove grate, which can be used to split the stove lines into groups and then other details from that point will quickly lead you to a positive identification. (It can go afoul if there are replaced parts, like pumps or fuel tanks.) I may be posting a very detailed spreadsheet style listing of each model and the characteristics, but we'll see what Ian can tolerate!
The Field Guide will not tell you what the stove is supposed to look like, for that info, you can use The Book, aka The Guide To Vintage Coleman Products, available at the top of the page.
*I spotted a mistake on the 416B line on the paper version, it has been corrected in the online version.
You can find the page at this link: http://intlccc.net/information/camp-stoves/stove-field-guide-2/