Gosh.. No idea, but with what appears to be a great deal of natural wear from being handled over the years, it seems like it would have to be at least 50 years for that kind of wear/usage.
Pretty incredible piece, the color and the design - rams are all I can see are very symbolic and sacred in nature to the Chinese and Japanese : ) Great item, thank you for sharing here.
It seems to heavy for plastic or resin.. I am leaning towards it being lacquer... There are no casting/mold lines that you would expect from something made from a mold.. No lines on top, bottom, or sides..
No problem.. Ask away ! There is a little bit of black towards the top, but starting about 1/4 " down into the neck, the rest of the inside is red.. I added a close up pic to better show you..