Atlas container pins

Have you tried wax? Or some of those non-permanent scenic adhesives? All you'd need is something to make a tighter fit in the hole.

I dont use anything, I tend to just stack pairs together and leave them alone. If I decide to swap around containers, I do it on a table with a towel so they pins dont go too far.

Yo can also Walthers GGO them in- using SLIGHT goo. When you need to take them out- then use Goo gone!

Ok, perhaps if I just exercise a reasonable amount of caution, I won't lose any. 

I can give that a shot.

A dab of Woodland Scenics accent glue. Its temporary glue, so you can put them in and take them out. 

Or just get a piece of correct diameter brass (or plastic) wire and cut your own.  I think they are around .030 - .040 but I don't really remember that I bought.