Walrich Elephant Bowl

First off I purchased this bowl because of the unusual elephant head handles. Now I am trying to find out more info on it. It measures about 6 3/4" in diameter and stands about 2 5/8" tall. It is an ivory color and shows overall crazing to the glaze. The part that baffles me is the signature on the bottom. I am pretty sure that this piece was made by Gertrude Rupel Wall cofounder of Walrich Pottery in the early 1900's. I have seen the GR and Walrich Berkley Cal. signatures but not this one. Can anyone shed some light on this piece? Is it a rare piece? Maybe a one of piece? How about the value of this bowl? I have contacted the Oakland Museum in California and am awaiting there reply. The museum is said to have a large collection of Walrich pottery and a number of pieces made by Gertrude Rupel Wall. Any info on this piece would be greatly appreciated. Thank you.