Many years ago, I purchased 150 South Vietnam ID cards directly from a source in Vietnam. These are for males, females of all ages issued during the war.
These were cards required for all South Vietnamese citizens to carry while the the war was going on... Of course, after Saigon fell, South Vietnam ceased to exist and all South Vietnamese "citizens" had their ID's taken by the NVA and new communist ID's issued. These previous ID's were apparently stored and then when the internet became a thing, a few thousand of these previous ID cards made it out of the country.
There are a few for sale on Ebay for $20 to $25 each plus tax and shipping...These would make great gunshow sellers for a dealer and display nicely with anything Vietnam related. I will take $8 each if you take all 150 of the cards. With some exposure, I would imagine a dealer could triple their money on these retail. These are all different and have Vietnamese citizens pictures, thumbprints, birthday and all vital information for ID from any soldier that asked to see it.
I also have German WW2 ID cards from various soldiers, Panzer, etc...I have had these for years and they would make a nice display with a K98, luger or other German WW2 items...$125 each. I think I have four of them.
There is a Hitler youth knife marked Germany... Not sure of the vintage...It has some wear. I will take $75 for it. WW2 Purple Heart medal with original coffin case...$125