Tartan authority - what can I wear?

[Shedlock2000]

Now, I know that no-one will hunt me down for wearing some clan's tartan. I know that 99% of people have no idea which tartan is which - there's so many! But, I get kind of sad in the mouth when all those with historic names swell up with pride because they are a "McLeod of the clan McLeod" and this is their tartan!

My last name is Firth. Which is Gaelic for 'tributary' (comes from the same etymology as 'fjord'). There aren't many of us, as surnames go; it's a relatively recent name. It first occurred in the early 1600's and originated in the Roxburgh region of Scotland. Indeed, we didn't leave that area - any of us - until around 1750-1800's. and then only in dribs and drabs. Since then, we've spread all over the world, with a lot of Firth's now living in the New York, Boston area (a huge amount of us shipped out in that time, it seems!).

Consequently, we wear a Roxburgh Red (or not any better, hunting green) District tartan, which is a sort of peel-your-face-off ORANGE and GREEN. Which is great, if you want Chris Hadfield to spot you from the ISS; not so good if you just want to look cool.

So, on my recent search for weathered and worsted tartans, I got to wondering - if I wanted to not step on any toes, if I wanted to follow propriety to the nth degree - what would I be permitted to wear?

I feel dramatically left out! Here we are, devoted border Scots, responsible for the Ryders of the Marches, defenders of the highlanders in the glitch that was Culloden (apparently, so I read, a few of the lower Edinburgh district and border outliers did not side with the English at the battle, but fought with the highlanders), and we don't have a clan to feel enraptured by.

I served in the mob, but with REME - and they didn't have a tartan. I live in Alberta - but have you seen Alberta's tartan?!? Even the national Canadian is a bit .... Meh. I just want to find something we poor unloved can wear, AND be able to answer the question 'is this your family plaid [sic. *sigh*] then?'..... Yawn, with something that fits their expectations, rather than something accurate like "actually, I just really like the colours".

Any advice, guys n gals?