Get the word out on local Facebook swap, car swap, barter pages for your area. Also, put postings in each major Craigslist for your region. Police don't have the resources to go after these thieves unless they are hitting multiple places and stealing tons of stuff. Be proactive in getting eyes of everyone looking for the sign. If you have close up pictures of the sign showing any unique damage that will ID the sign that helps. But a sign in frame is definitely more unique.
I also visited all the local flea markets and told dealers & friends to be on the lookout.
I hope you get some leads and get your sign back. I'm still working to get my trailer and 25% of my stuff back.
