Talk to their guys... they can get them. There is a lot of stuff you can get from Sweetwater that they don't advertise. There is one high end electronics maker in particular that comes to mind...
Nick,
TG stands for tour group. Mic's with the tg prefix are suppose to be a little more heavy duty to better stand up to rough use received on the road. That's how Beyer explains it. Anyway I have an older non tg m201. Got it used, love it. It's a great all around mic much like a 57 only more hi-fi sounding. Stick it any where you would a 57 or any mic for that matter and see if it gives you something you like. Dave