Probably not what you’re looking for, but I find the mini French baguette breads used in banh mi to usually be pretty crusty and hard. I heard Banh mi Ba Le in Dorchester used to bake their own; but not sure if that is true or still true.
On a side note, I must be one of the few people who does not like overly crusty, hard bread. I don’t enjoy eating with the roof of my mouth all scratched up. 
