Since two out of the three people that read my blog have checked in, and the third should know the answer from listening to Moonrabbit and I talk about it...
The item is a Navajo water drum! Apparently made between 1920 and 1940, they were filled with water to various levels for different pitches then covered with hide. It is covered in pine pitch to make it waterproof.
The appraised value is $750.
This was an item in my step fathers collection that we are donating to a Native American museum. In the few notes we found, he thought it was a cooking pot.