Looking at the documentation I would say NO:
* the only legal parents of a canvas is a window or frame i.e. a canvas can't
be inserted into a button
* the button has no gif option and neither is there such and option in the list
of generic options that any widget can use.
Your best choice is to either use ascii chars "<" and ">" as arrows or use
something else than gs, for example etk, java or some other graphics library.