Sepia Charcoal Soldier Rendition- Whose Army and Regiment?

We found this very interesting soldier in a flea market many years ago and we never had the opportunity to find out more about him. He is drawn in Sepia Charcoal and is in a 1920's 30's wooden frame that measures 12 3/4" by 16 3/4" high. I thought he might have been in a Scottish Regiment because of the hat and pompom but it appears to have a crest on the side of the hat. The uniform looks like a US Forces issue but we really don't know. It was found in Canada but I don't recognize the uniform as being Canadian. Does anyone recognize the uniform, the regiment, the army or the time period it would represent. I have photographed the painter's initials (SD)? in case someone might recognize it. Thanks everyone.