I really liked
Sk-Jukebox (Windows) page flipping system very much. Its very cool, even it simple. Just been sad its discounted.
In my own software,
MultiJuke (Windows, Linux), its use 30/60fps smoothscrolling instead of page flipping (when Jukebox GUI is used). Here I highly recommend a spinner, but it work perfectly with 2 arrow keys.
I haven't see other software that used animations or scrolling to page flipping, debited there is other good button based jukebox software out here without these animations?
These arrow based buttons seen to been gone on HappControls, since I also remember they did have them before. They was really cool to use as page flipping. For numbers, you might could hack a numpad and/or use costume illustrated buttons?
[EDIT]
Very hidden, I asume you tinked about this triangle button (found from one of the show us jukebox links)?
http://www.happcontrols.com/pushbuttons/710004tx.htmThe link to a other simular projects with happcontrols used buttons (numpad + triangle) is here:
http://forum.arcadecontrols.com/index.php/topic,17979.0.html