Does anyone know if / where it is possible to buy a metal locking post for the birdlocked ? The plastic on the Mk 1 version was ludicrously thin and so they just snapped. The new, Mk 2, is thicker and much better but a metal post would be so much more secure. By the way, other than that I realy like the Birdlocked: a bit fiddly to get on the first few times - but there is a knack - very comfortable to wear and, for me, really quite secure.
Not much help because i realize you want to only buy the pin and not a whole device, but this CD that I ordered to temporarely replace my jailbird as its being adjusted comes with a metal pin that can also be used with the birdlocked: http://wholesalebdsm.com/ProductsView.asp?id=450 Maybe some hardware store has a little pin like that or contact the seller on that website if he iswilling to send you just a pin for a few bucks?