Sockfish, I ordered my replacement from a similar site (or perhaps the same one you found) at a similarly horrible price.
Have you considered the led wholesalers site? (You would put the two words together plus dot com).
You can mount a bunch of rigid, somewhat insulated lights on your burnt out light arm with zip ties.
I am somewhat selfish in mentioning this because I am looking to sell my lights that I did this with on my Edge 6 gallon.
The only reason I am not still using it is that after a spectacular HVAC outage at work that went on for six months and killed all my fish, shrimp, and 2/3s of my plants, followed by cold that created excessive condensation, the 2-prong part of my original light arm rusted out and the leds on my superbright mr11's came unglued.
The led wholesalers light strips are okay, though.
I decided, upon restarting my tank properly last week, to upgrade to the 12 gallon replacement light arm.
So...if you are interested in three functioning strip lights and all connecting parts, including transformer, pm me. Also, I have my old light arm which may still work, and I'm willing to mail it to you at cost of shipping if you want--you could change out the sockets and put some crazy strong led's in there, maybe?
Elsewhere in this thread people say you may need a different transformer for that, so I'm not totally sure if that would work, though.