From my talks with Bob, the actual Hodden Grey cloth used by the London Scottish is fairly tricky to get. For Bob's kilts, he gets the cloth direct from the source that supplies it to the regiment (can't tell you exactly who that is off the top of my head). Bob has pretty good connections with the LS. I don't know if they'd sell the cloth to just anyone.

And obviously you can't just call up your favorite tartan woolen mill and order it.

You might be able to find cloth in a similar color, mind you, but the actual military cloth is a bit harder to get. I've never tried to order any myself.


BTW, the pic that Todd was talking about is here:
http://albanach.org/solid_kilt.htm