Dr.SleepRoch said:

My experience ordering cross-border ordering internationally: I've ordered from a Canadian pharmacy.

This is where I part company with the consensus forming above. Import rules are jurisdiction-specific and this board keeps giving US-shaped answers to non-US questions. What is a personal-import allowance in one country is a controlled-import offence in another.

Adding the numbers, since they settle part of this. Worth stating the units and the reference range whenever you post a number here. A large fraction of the apparent disagreement in these threads is two people using different units and both being right.

RetaRick_CA said:

Import rules are jurisdiction-specific and this board keeps giving US-shaped answers to non-US questions.

There is a second half to this that has not been said yet. Start from the measurement rather than the conclusion. Almost every disagreement here turns out to be two people measuring different things and comparing the numbers anyway.

Correct me if the detail matters more than I have assumed.

A narrower follow-up, since the general answer is now clear:

How long did you give it before you decided it was working?

Closing the loop on my own question.

Reporting back for the archive rather than for the thread: I did the narrow version of what was suggested, gave it the full interval, and it settled. Posting it because threads without a follow-up are half a thread.