I've seen a variety of pleco labeled as a zebra that wasn't the well known rare Zebra, looked nothing like the rare one, but was selling for around $50... It wasn't the real zebra. Probably best to pay attention to the L number associated with the one you really want so you don't end up surprised with the wrong fish and yes, the $300 variety is extremely rare. If you can even find one online its a find, let alone in stock at your lfs
Expensive rare zebra pleco is L-46
There is one called a chocolate zebra and sometimes just called a zebra that is less expensive but is not a true zebra pleco. Its L # is L270
There is also one where zebra is thrown around loosely called a Tapajos Zebra Pleco that is L307
I'm willing to bet if you saw one at your LFS
and it was less than $200 it was one of these varieties they use the zebra classification very loosely
Also, finding a true L-46 for $399 isn't terribly bad. You can see at live aquaria .com right now they are $500
I'd crap if I could find one for $200! Granted I wouldn't buy until I had the perfect environment for such a rare fish.