hooray! congratulations Andrew
your balance is a minimum +500$ above the purchase price if you bought it for the average ebay price. (what was it btw?

)
this would be a rare model and it might be possible that the caseback is original with only Stainless Steel and SN# written on it.
btw. why would TC produce a solid gold watch with a steel back? a version for the "poor"?
if you don't think this caseback is original then what would an original one be stamped with? "14K Gold case, Stainless Steel back"?