Some very nice original postcard illustrations by Archie Gunn (1863-1930) are coming up for sale at Swann Auction Galleries’ June 5 illustration sale. They are lots 86 to 89.
See pulpartists.com for a good biography, https://www.pulpartists.com/Gunn.html>
Archie Gunn was a prolific illustrator. See CardCow for more examples:
The originals watercolors are followed by the postcard reproductions:
Miss Canada, also known as Miss Toronto
Bride of Niagara
Rolling Skating Girl