Vintage White Dapper Dog with Polka Dot vest from Grandmother's 30 yr collection

When Mom passed this year, we found a box of my Grandmother's dog collectibles. All were wrapped in Miami newspaper dated 1963 so everything in the box we know is older than 1964 at least - all wrapped in same paper and since only 1 'layer' was used some were regrettably damaged).

Not an expert on dog breeds, nor collectibles. I found this site when I was looking for help in identifying vintage costume jewelry I inherited from both my Mother and Grandmother.

Super cute...the name of the breed is on the tip of my tongue!! No mark, just the #37 written in pencil on the bottom. Help with verifying breed and possible decade/maker is appreciated!