Mint, You can try to re- collimate them yourself just by slowly applying pressure (up/dpwn), to each side whilst looking thru them. Unless you have dropped them the prisms should still be O.K. If you do not want to try this then try DAW in Sydney. Have you tried a local optometrist re; info.?
http://www.daw.com.au/
HTH.

L.
ps. Thanks Beren. I thought there'd be a local guy.