Question about amp price...

Hey, so I have a 1975 session peavey 400 with original knobs and faceplate and electronics in it, in mid condition. I wanted to know what a good selling price for it was...I did some research and am thinking of the $300-$400 price range...but those amps didn't have the original faceplate or knobs. Would mine sell for more???

Bump...I need this question answered by tonight!!!