Welcome to the site, nice find. I am by no means an expert, as I am new here too, but I have seen these come up for sale periodically as I am always on ebay for work.
There is one in pretty rough shape, worse than yours for sure, listed for $750. It has a few watchers, so people are keeping an eye on it, but I would say that's too high. In your condition, I could see someone paying in the 500-750 range because it's shell and it's a less common sign. If I owned it, I would have it for sale in the 750 range and take offers.
But again, just my opinion. I'm sure someone with more shell knowledge will chime in. Anyways, cool sign, good luck with whatever you end up doing with it
Here is the busted up one on ebay, item number 302264286599
Edited by thebmwjunkie (Sun Apr 09 2017 05:44 PM)