Terk XM....where can I buy?

I have Sirius installed in my '07, and I want to drop XM in there since we need to swap the house radio for an XM unit and I'd rather not pay for both. (Yea, I know they're one company....but bear with me)

So....a few years ago there was a cheap (about $ 200) solution from Terk that apparently is not available any more. I checked eBay and came up empty. Anyone know where I can get one? Or should I suck it up and get the $500 (gulp) Toyota solution?