I don’t know of any online since I buy mine at a local shop. I’d look for any that mention they’re implant-grade and to what standard they’re compliant with. In regards to standards, I can personally vouch for ASTM F-136 but there’s also ASTM F-67 and ISO 5832-3.
It’s been going well! I received my passport yesterday so I’m planning a trip to see some friends in Canada for later this year. I’ve been struggling with my book goals lately too but I’m ~250 pages through Priory of the Orange Tree and loving it.