Lo65! Welcome to the forum! It looks as if your Flatgate is a 4th type instead of a first type. The type 1 Flatgate has a non-serrated front sight blade and all of the others have serrated front sights. Also on the 1st type, the Single and the Six that is stamped on the side of the frame will not have a hypen between the Single and the Six. All of the other types will be stamped with a hyphen such as "Single-Six". The Type 1, and type 2 will have a short throw ejector rod housing and the type 3 and the type 4 will have the long throw ejector rod housing. Also the type,1,2,3 will have the small serrated ejector rod button and the type 4 will have the large dimpled ejector rod button.
Your gun appears to have type 4 parts. RENE list your gun at $630 if it falls between 95 to 98 percent. As your gun doesn't appear to be in that good of shape then some decrease in value will occur. That will be determined by how bad someone wants it and how bad you want to sell it. :roll: