I wrote the entry on Paige for the Mark Twain Encyclopedia, so I looked at
all I could, but I don't remember a photograph.  Of course, I wasn't
specifically looking for one, and that's been awhile.  I know if anybody
will find one, Barb will, since she found the birth and death dates for
Paige that I searched for for so long and so long and so fruitlessly.  (Of
Paige's prospective death, MT said if he had him in a steel trap, he would
cut off all food and water and  "watch that trap until he died".)

I do have a description of Paige by Paine:  "A small, bright-eyed, alert,
smartly dressed man, with a crystal-clear mind, but a dreamer and a
visionary."  So that's who you're looking for!

You might try looking for a picture in one of these:

Roger Burlingame, Engines of Democracy (Scribner, 1940)
John Smith Thompson, History of Composing Machines (NY, 1904)
Waldemar Keampffert, A Popular History of American Inventions (New York,
1924), Vol. I, pp. 228-233.

A stab in the dark, but might help!