This is a creamer from the Uplifters social club. The Uplifters was founded by a group of businessmen in the Los Angeles area. L. Frank Baum was one of the original members and was quite active in the group, writing several plays for the members to perform and contributing a few poems and pieces that were published in Songs of Spring, a compilation of poetry from some of the early club dinners. The Oz Film Manufacturing Company had financial backing from some of the prominent club members. The first Uplifters dinner was held in 1913.

This particular creamer may well date from after Baum's involvement with the club as he died in 1919 - but there's always a chance it might be from some of the earlier dinners!