What can I use as a substitute for canned refrigerated biscuits in monkey bread?
Using refrigerated biscuits for monkey bread is actually just a convenient shortcut - if you don't have pre-prepared biscuit dough at hand, you can simply make your own sweet yeast dough from scratch, that's the classic (pre-Pillsbury-can) recipe.

Either find a recipe that uses sweet yeast dough from scratch or substitute your favourite sweet yeast dough. (The Wikipedia page linked above has a link to a recipe, for example.)