I don't think IQ car audio is in business anymore - I ordered mine from them a few years back, but it sounds like they have closed doors in the last year.

It looks like Distinct USA is the current authorized distributor of Rainbow products in the US. Try their website here:

http://www.distinctusa.com/contacts.html

You can also try La Jolla Audio, they used to be a distributor of Rainbow a few years ago, they may still carry the line:

http://www.lajollaaudio.com/home.nxg

Also, just FYI - the speakers that were sold under the "IQ" series for the 124 were the Soundline coaxials (SL120). The rear speakers were the same size, but with a bracket to fit the slightly bigger speaker hole.