How and where to sell and antique firearm from WWII?

I have a Browning M1919 machine gun that has been de-ammunized by welding. It was left to me by a friend leaving the country and I would like to sell it but I am at a loss as to how/where to do so. Craigslist and Ebay have rules regarding weapons even if they don't fire. I cannot find any gun shops nearby that will take antique gun and I'd rather get more money by selling straight to a collector. Any ideas?