bb's don't normally fail on tour, and even if they do, you should
have many hundreds of miles of notice before it becomes unrideable.

i had to google isis bottom bracket, never having seen one.
looks like an octolink but google says not compatible.
china taobao has a few expensive models, 5-10 times the
cost of a sealed bearing square taper.

where i prefer to tour (cambodia/laos/myanmar), square taper is
all you'll find, in a few common widths. most will be cheap
mainland chinese carp, sometimes you get lucky and find
some taiwan product. could probably find isis here in bangkok,
but mucho trouble considering the size of the city and the
language barrier.....so far, i can say "i want spicy pork" and
"i like geckos" which is sufficient for most situations.