Rummaged around the net for it just now too, and came up with this:
Model: 70-1786 Metra

That's the one apparently that crutchfield ships as well, so now I just gotta find this thing in a store around here somewhere. I went out and got both the male and female antenna adapters just in case, the removal tools, and regular speaker wire adapter for good measure. Now just to hunt down the RCA adapter and see if that works better like you suggested.