Sorry to arrive late...

IMHO, the two brands that should've been mentioned are: https://northstbags.com/ and https://black-star-bags.myshopify.com/

Both brands are fabricated right here in Portland, Oregon (where both thread starter jyl and I coincidentally live).

You can buy their bags off the rack in the better bike shops around here... or directly from the manufacturers. Black Star bags are AWESOME. A bit more radical. I ultimately chose a North St. "Morrison" backpack pannier for my bike. (North St. also makes a model called "Woodward".) It's a really nice size for when my commute requires carrying a laptop and/or dress shoes. Plenty big. Keeps my stuff dry. I don't find I use the shoulder straps as much as I thought I would.