Before my hikes I Google search for shops in my first village/town and phone to ask what if they stock meths or white gas; maybe even try a contact in the local Chamber of Trade for advice. After flying I have the similar issue sourcing Methylated spirits for my alky stove. I don't do gas stoves on long hikes because of the availability of canisters. Meths can be a problem but I can use twigs at a pinch.
However it can go awry in Castlebay, Hebrides I rocked up to a Co-op to get some only to be told they hadn't any; I said you told me you had two weeks ago; lady said we did two weeks ago, doh. A local opened up a shop nearby to get me some - just when I thought about getting some twigs.
In Montreaux I walked off the train straight into supermarket who had meths.
The other issue with Meths is disposal of some at the hike start as it may come in a heavy one litre bottle; looks very suspicious ditching some at an airport. In a rushed airport departure in Stornaway the check in desk told me to flush it down the toilet.