Johnny Unitas - Golden Arm print

This watercolor print is very similar to a famous picture I believe was taken by Sports Illustrated photographer Roger Riger early in the sudden death overtime of the 1958 NFL Championship game. The game many refer to as "the greatest game ever played". In addition to the game scene, there is a large Johnny Unitas headshot in the background as well as a printed signature saying "Sincerely Johnny Unitas". A couple of weird things about the picture (in my opinion) are the absence of the Baltimore Colts logo on the helmet and the NY Giants uniforms look like SF 49ers uniforms to me. I guess even then the NFL controlled any duplication? The print is about 17" x 20" and is printed on a thick paper stock and is in excellent condition. It is signed by an artist but it is difficult to read. I can make out "Frank S_ _ _ _er". The other letters could be R or K, I, N and/or D. The copyright on the print reads "Copyright 1968 Jack Webb Corporation Bondville, Vermont o5340".
I've had the print for at least 20 years. I had it matted and framed about 5 years ago and had them also add my 1969 Topps #25 Johnny Unitas card in the lower left to make a nice display.
I grew up a Baltimore Colts fan so I really love this picture but I'm wondering if anyone knows anything else about the print itself. It seems unique to me and I've had trouble tracking down the artist or the printer. Any additional information or comments wold be appreciated.