We found that none of the LOINC AnswerLists are not available via tx.fhir.org, but it seems like they should be. Zulip thread (discussing the issue and the import code referenced by @grahamegrieve : https://chat.fhir.org/#narrow/stream/179252-IG-creation/topic/Found.20multiple.20matching.20profiles.2E.2E.2E/near/271010376