Here is a Mack Bulldog sign that is no doubt a repop. Known versions have a green back. I did a lot of research on this sign in order to get my money back from an auctioneer who sold it as original. 190500356098
These were made to look old with all the rack marks (more than any sign I own) and the old style hanging brackets. Always in mint shape. It's a shame people are getting burned this bad. I myself paid $2400 and the auctioneer had the crowd applaud my purchase. Took six months but I proved my case and received a full refund. It stinks you can't contact the buyers anymore on ebay. This site is worth it's weight in gold (not sure what a website weighs but my computer is heavy) for this and all the other valuable info.