I don't think I have ever seen the ones Tom sold, but they sound like the pins that are pretty common among the free flight arena. You might check out Peck Polymers and National Free Flight Society. The ones I have all have orange heads. I don't know what area of use they may have crossed over from but they always reminded me of the pins used to mount insect examples on a board or display of some kind.
Type at you later,
Dan McEntee