Holy crap, a size 17??? How tall are you? My brother is 6'8" (and 290 lbs!) and he wears a 17. Of course he has tons of trouble finding shoes as well, but he's lucked out and made some friends who are Nike product reps who bring him free shoes every once in a while when they visit.
I can't imagine letting my brother ride my bike (when I had a 919), it'd be like a clown bike for him.
Good luck finding some boots, sometimes it really does pay off to be completely average.
'07 Ducati Monster S4RS
'06 Honda 919 (sold)
'95 Honda Rebel 250 (sold)