Saw this at an antique mall today.. They have a little over 500 on it.. Is it the real deal, and or a good buy?

A few things to consider are: Are there known repros, mounting hole size and location, style of grommets (if used at all), dimensions, single or double sided, font, color, how/where the sign would have been used.
What are your concerns about the signs authenticity?

What someone says it's worth does not determine if it's a good deal or not. If it would put a smile on your face to own it at that price then yes, it's a good buy.

Yes there are known repros of this sign. The border looks a little funky. Would need some better pics to be sure.

The funky areas on the border, the lettering and the blue field are chips that have been touched up.