Over $50 for a walking foot????
I've never even seen that brand before. Maybe they make generics for someone else. I'd be extremely hesitant to buy one sight unseen. I have the feeling if you asked about local dealers, you'd get a whole lot of runaround.
My vote for most popular in US is probably Singer, although the quality is not there anymore. My rating is based solely on the fact nearly everyone has owned one or more Singers. Based on sheer number of machines sold, it probably leads also, since every WalMart carries a Singer.