The British got themselves their Mobile SAM Launcher the other day, but SAM launchers aren't really going to be able to take and hold ground. I mean, I guess they could, but it wouldn't be very effective. No, for something like that, you'll want to get the British Mechanized Platoon for your Team Yankee army.
This set comes with four GPMG teams that are equipped to fight against tanks. Then there's the three Carl Gustav anti-tank teams (I assume that means everyone in the unit is named Carl Gustav. It has to be rather hard to form said units, I would think. However, the camaraderie that would come from such a set-up would be invaluable. However, roll call could be confusing). You also get a mortar team. The set matches well with the standard rifle platoon section, and can thus be easily carried by FV432 APCs.