Cknight: howdy do old pard. Nope, they never came in the 4 and 5/8, that I know of. I think when I got mine (couple of hundred years ago) they only came in the 7.5", but then later on came out with the 5.5".
For close range thick brush hog hunting the 4&5/8 sure would be nice, although I think the recoil would be similar to that of any 4 inch 44 mag out there. Also, I doubt you would lose much velocity with the 4&5/8, and it sure would look cool. I saw one like that the other day and they do look nice. HTH. Mikey.