well you have to realize that the following items pertain to every item that can be collected.
1. how many were produced?
-if 30,000 were made chances are that many will have been deemed unusable and destroyed in the 90 years since they were made.
2. how many exist?
-if all 30,000 rifles that were made still exist, its easier to find one somewhere. if only 10,000 survived the 90 years since manufacture, it will be hard to find.
3. were are the surplus weapons at this time?
-importation laws prohibit various countries from sending weapons into the free world. as a result if the weapon is in a prohibited import country, you cant get it.
4. the importation of old guns is cyclical. for example if the intended customer segment is 20 year old idiots who want semi autos, the import companies will grab all the old semi auto aks and sks they can find. and leave bolt guns alone.