The age of most mudmen are older than the mudman.  The vast majority were made in the 40's and the 50's.  And yes, they were merely stamped CHINA.  They were so worthless that when a shipment would arrive at the BXs at the military installations in Hawaii the poor little mudmen would be dumped out on to a countertop with a shallow edge.  No care given to avoid breakage.  After all their destination was a aquarium.   Then in the mid-50's you started  to see Made in Hong Kong, and other markings.   Truly  old  mudmen have remarkable details.  You will find an undershirt with a button for closure close to the chin at the  neckline . This will be under the tunic you normally see.  Fine fingers,  well shaped high cheekbones,  and a glaze that feels of quality. When you see an antique mudman it will catch your breath.  And often it will have the original wood carved base that is a perfect fit.  Good hunting.