Can I use my vulnerable sector check for another position or an organization outside Canada?

Not automatically. The RCMP says each position requires its own check, so if you apply for different positions that need a vulnerable sector check, you may have to submit fingerprints separately for each. It also says results are only made available to organizations located in Canada.

Source: https://rcmp.ca/en/criminal-records/criminal-record-checks/vulnerable-sector-checks