Hi Dave, welcome to the forum.
I'm not going to have good news for you I'm afraid-that is no Heuer. Parts that claim to be 'Heuer' have been forged sadly. I can be more specific about certain elements if you wish, but hopefully you are covered under Ebay/Paypal buyer protection to have it returned.
Best of luck!
Steve
Oh, sorry, it's a 7734. Which is the same as the 7733 only with the date function. I didn't see a date feature on the dial! 😀
That's a Valjoux 7733 movement, which was used in some 70s Heuers, but also in a lot of other watches as well. Agree that this one is a forgery.