Eckstein,
I'm coming late to this thread but here are two (very poor) images for George Washington "Grin" Bradley. These are both from group collages so a lot of resizing will be necessary:
http://www.bluecurl.com/ncbbp/search.asp?search=bradley
(top image= the Bradley headshot is very fuzzy when enlarged)
http://www.theruckerarchive.com/
No direct link for this one, but do a search for the 1883 Philadelphia Athletics. Bradley is at 3:00 in the ring of portraits. The names on this one are illegible, but trust me on this (I've figured out IDs for everyone else in the collage except the center people, who seem to be the team owners).
And, since we seem to be working on the same project: did you ever find images for Dory Dean or Tricky Nichols? SABR's pictoral history project says that pictures of these two guys exist, but I've come up empty looking for them.