CanadaStamp: Postal stationery prices have risen over the past few years. Yes, there are some that "command" low pricing, but the large percentage of items go far above the H&G value of 30 years ago. Look at Germany, 4 Euros+ each (mint). GB 2+ pounds each (H&B catalog). US and other NA countries, are in the NA mind of pricing (Low). Take a look at aerogrammes from the Pacific Islands, Middle East, some Africa, they are quite pricey! Far higher than $1.00 will get you, mint or used. Go over to
ebay , DeClampe, etc and look see how much these items go for.Generally speaking, larger countries issued hugh amounts of postal stationery, where little 2nd or 3rd world countries did not. In most world cases, mint commands a lower asking price than Used as you mentioned.
There are exceptions to this rule as well.
Additionally, since the aerogramme is a thing of the past, a lot of new collectors are getting into collecting these items. Flyspecking them. Looking for rarer cancels, etc.
SO, I guess the more people that do NOT collect these things, keeps the price down for the ones that do.
This is just a reference comment.