I do not believe that price is fair. I think it was extremely high for what the drums are. If they were a rare matched ROUND badge kit, and was in excellent original condition, then you would have a "fair" price. I think what you got was an assemblage of orphaned drums. Sound-wise, they will still sound like Gretsch.
What would I have paid for that kit? Well, as a "player's kit", I would probaly be willing to spend $600-$1000 IF that little 18" bass drum has not been altered. I don't know Gretsch stuff very well, but that tom mount on the bass drum is partially covering the badge. I can't imagine that was a factory installation, but, again, I could be wrong. If it was altered, then I'm at the low end of the price range.
Another curious question is the title Gretsch "Jazzette". Did Gretsch make a kit called a "Jazzette", too? I was under the impression that was exclusive to Ludwig drums.
I don't mean to be discouraging. As David stated, we have probably all made some "less-than-perfect" deals in our day.
I can't advise you about legal issues. Good luck.