I don't know about the restaurant Sambos, but the name was surely taken from Helen Bannerman's book. The book is still in print, actually. I have both old and new copies available for sale. I especially like the book illustrated by Eulalie. I want to give it as a baby gift to a dear friend.
Book is small, Red cover with black writing and picture on the front.
Need one in pretty good shape. I know there are some of those out there. I've already been stung once. I had one as a child that was made of a heavy paper with lovely pictures. It is such a cute story.