Airguide 712-B for parts

I have an Airguide 712-B that I found in my Dad's garage. It has the original box and instructions but it apparently got wet at some point. I don't think it was ever installed or used The lens and dial are essentially perfect, and the bezel is nearly perfect except for some discoloration on the bottom surface, there is no rust. Inside, the back plate is rusted, so I doubt that the mechanism is functional. I think that the parts are worth about $50 based on what I've seen on other sites. Make me a reasonable offer before I put it on Craig's list. Thanks

Another one gone, another one gone- another goes one
To Steve

This will look sharp in your restoration! You'll need to hire me to find all your gauges now.😍