Gday Martin
OPT in the states normally stock the ASII hbxs
http://www.optcorp.com/product.aspx?...=autostar&st=2
They state its in stock, but dunno how true that is.
One other thing to try first.
If your Hbx is an older model, ie the contacts on the PCB are just
tinned ( vs gold flashed ), then using a soft eraser
to scrub off the oxidation that forms on em can restore the
functionality of the keys by an amazing amount.
I have to reclean mine about every 4-6mths to keep the hbx
working easily.
Andrew