Sometimes HRT suppliers get targeted to get taken off the public internet, so some suppliers make their servers accessible via TOR, which provides anonymous access that can't be blocked easily.

Use the Brave web browser, and from the menu select "New private window with TOR". The .onion URLS below will be recognised in this new window.

TeaHRT: http://3wtouidqubrwl57lcckyiwc3dhjo7bpuflhbmvvrvkmu6cwpzg7ht5qd.onion/

ClearNet suppliers

Voix Celeste: https://voixceleste.cc/shipping/