In my early Kilt days,
I bought a 'Pride of Scotland' tartan kilt from a company by the same name. It was fine, no complaints at all.
Also a Denim Kilt from 'Camo Kilts' likewise o.k.
and a couple from I think it was 'The Kilt store'.
and of course 'Frugal Corner'
I got a Utilikilt from Ebay too.
All were on EBay, and all were most satisfactory.

These days though, I tend to go direct to websites, and still shop at Frugal Corner & Stillwater Kilts direct, as well as others.