If they are the "push-on" types & not the "screw-on " ones, then what you have is called the "M-201(A/P 25S-5A)" or commonly called the "Gyrojets". They were first used in the latter days of our involvemnet in Vietnam. The old "screw-on" types(M-185/A/P22S-USAF isuue and the Mk-79 Mod 0-Navy issue) were found to be inadequite in penetrating jungle canopy that could be as high as +300'. Gyrojets were then tested and found to be very adequite in penetrating the jungle canopy for SAR to find you. They also went higher to around 1,100' and burned for approximately nine seconds. The others only went to a height of around 200-250' and burned for only five to eight seconds. As far as finding them, they are out there, but you have to know where to look. They are expensive(anywhere from $100 to $200). If kept in good condition they will last for a long time and make a perfect addition to any "survival kit". And "YES" they are highly collectable and sought after by people like myself who collect "Aircrew Survival Equipment". Any other questions?
Mantracker