Picking up on something else that Jock Scot wrote, concerning the Atholl Highlanders: “. . . interestingly they make a large ‘thing’ about obtaining permission to wear the Murray tartan from the Duke of Atholl.”

The Murrays of Atholl were involved in founding the Transvaal Highlanders (raised in Johannesburg in the aftermath of the Boer War), and that regiment still wears the same tartan.
Three sons of the then Duke served in South Africa, and I believe they also all settled in this country after the war.
The present Duke is descended from one of them, and is resident in Limpopo Province, in a quaint little town (originally a 19th-century mining village) called Haenertsburg.

I believe I also saw a mention of the Hunting Stewart being worn with permission. The Pretoria Highlanders (formed immediately before the Second World War) wear that tartan as well (with permission).
Regards,
Mike