EuroW at Costco are nice and so are the Turtle Wax Emerald Series. Both can be found locally for pretty cheap. Just be sure to feel them first and get the softest ones. I can not see spending $15-20 before shipping on a mitt when the one locally do not cause any problems.
If you have the newer Meguiar's lambs wool mitts and not the synthetic mitt, then you have one of the best lambs wool mitts available. If I were to guess, I would say they are made for Meguiar's by SM Arnold. If not, they sure "look" very similar.