This is really just an advertisement for a fellow Aussie providing a great service for Nerfers in Australia and the US (for now, may expand to worldwide).
SlyDev is an Aussie based store which utilises 3D printing to make reasonably small Nerf accessories which have been experimented a number of times and calibrated to fit perfectly on Nerf rails (or be glued on to blasters).
He makes accessories such as tac-rail mounted iron sites (which I'm very interested in), a tac-rail mount for a Jolt (which I'm also interested in) and the Companion Cube from Portal.
The store link is this
blue underlined text.
Fellow Aussie blogger Rolley (who runs Street Tag Warfare, link left) has gotten a bunch of the accessories SlyDev sells, and has two reviews:
Jolt mount and
Iron sights + other stuff.
Postage in Australia is capped at $6 (an absolute bargain) and to the US postage is a flat rate of $13.