Apparently "Tompkins" is Cubs 1968 #1 draft pick Ralph Rickey, who was being converted from outfield to pitching during Spring Training in 1971 and thus drawing more press than a guy who had never (and would never) make the Show normally would. Tompkins has this little "ear-slash" thing that the #59 in the picture doesn't have (although you can't see that part of the ears in this picture, but there are other pictures of the player on Flickr, apparently).
Archie Reynolds has wispier eyebrows and his nostrils aren't as flared. (He also has the "ear-slash", too.) Besides, he'd worn #46 during 1969, so it would be odd for him to get kicked up to #59 during Spring Training 1970 (the first training camp where these uniforms were available, as the Cubs didn't wear this design until '69). As it turned out, Archie wore 39 (the number he'd worn during his 1968 debut) in 1970, so he went down, not up, numerically.
Oh, well.
The quest for Tompkins in color goes on, apparently.