as far as i can remember puri-tabs are chlorine base tabs wrapped in a mylar foil, so why repack them ?
if you are talking about iodine based tabs, iodine and steel don't really mix well, as far as i can remember...

on this site doug wrote a article about repacking iodine tabs, so check it out: http://www.equipped.org/parepack.htm

you could ask for those glass vials at your local chemist.
if you can't find those glassvials, try to look for toy chemistry sets, SOME of them got the right glass vials with teflon O rings. ( give the rest of the set to your kid or somebody else... )