Matt, Barb T., Rocky and I use D.C. Dalglish in Selkirk, Scotland when we need a special weave of fabric done.

Dalglish will, for a price, weave a single 8 yard length of single width fabric of any Tartan you can supply the thread count for.

Most other weavers will weave your fabric for you but many have a minimum yardage requirement of about 16 yards double width or enough fabric for four Kilts.

If you have not talked to a Kiltmaker about your Tartan I would suggest you do so. A Kiltmaker looks at the Tartan pattern differently than a designer.
You probably were most concerned with colors and their meaning. You may not have looked at Sett size or the symmetry of your Tartan which makes a big difference to a Kiltmaker.