Try the interview with Bringhurst at:
I published some work in a London magazine, MARGIN, back in the 1980's which also contained some pieces by Bringhurst. Try looking for indexes of that magazine.
Canadian writers are very co-operative when contacted directly; they want to be known by the rest of the world and seldom are. Perhaps you could write to Bringhurst via the address on the interview site.
Bringhurst's article in Robin Magowan's MARGIN was called "Breathing Through the Feet."