I didn't know you were in the market for one, I'll keep an eye out on the boards.
I found Monitor, Supergirl and Flash at the TM on Hebron and Old Denton a little while ago. They had a second Monitor there, would've picked up SG or Flash for you if they had extras. That store also had Megs, and a case of Lego CMF Series 7. Frickin goldmine for me!
Cool, TRU Frisco had a full case of Series 1 in case you're looking for your last two. They also had the Prime and Bumblebee Beast Hunter sets, but no Trailbreaker and Windcharger. And no GI Joe Kre-Os.