Ninety-nine percent of the time, my luck on eBay has been very good. I bought my daughter's wonderful Singer 401A from a great seller on eBay who turned out to be a QB member.
And i found my beloved Singer 301 there too.
I did hit one doozy of a bad seller when I won an auction for a pristine Rocketeer at a low price. She actually tried to pass off a rusting mess of a Rocketeer with a different serial number as a substitute. She sent it wrapped in a very dirty, hairy bathmat and nothing else! When she refused to answer any communications, I opened a case and sent the folks at eBay comparison photos. eBay was terrific. They gave me an instant refund, including shipping costs both ways and then they went after the seller themselves. eBay has done a lot in recent years to make it safer for buyers.
Sorry you had such a disappointment...but keep up the search!