Although some military tartans are now used as clan tartans, MacKenzie (ie: Seaforth) was certainly a military tartan before it was accepted as a "clan" tartan. The bulk of historical evidence points to the fact that prior to 1778 (the date of the raising of the Seaforth Highlanders) MacKenzie tartan was red, not green. That over the years the Seaforth Highlanders tartan came to be adopted by M'Kenzies as their own is not in dispute; but to suggest that Seaforth is a variant of MacKenzie is really putting the cart before the horse!

The same could be said of Gordon tartan which is a military tartan adopted as a clan tartan, but which is nothing like earlier specimens of the "clan" Gordon tartan.

As far as the green waistband is concerned, I rather doubt many civilian kilts (in any tartan) were supplied to customers with a built-in "army surplus" look. While an ex-serviceman would have no objection to wearing the kilt he was de-mobbed in, a civilian would probably insist on something less MODish.

Based on the photograph the gentleman either bought a kilt at the Leith Army Stores for a fiver, or served in the Seaforths and continued to wear his kilt after leaving the army.