Thinking of Buying a Vintage Seiko SQ — Should I Worry About Fakes?

Hi all,
I'm looking at picking up a gold vintage Seiko SQ (Quartz) on eBay, and I’m seeing prices ranging from around $60 to a few hundred dollars. I’m not too familiar with the counterfeit market for watches in this price range — especially vintage watches — so I was wondering if fakes are something I should be concerned about here.

Any advice on what to watch out for or how to verify authenticity would be really appreciated!