OK, finally a N. American source for correct Jacobite-period knitted/felted bonnets - and at a great price! X-Marks member Arlen's fiancee Diane is adding these bonnets to her line of kilt-related knit goods here:

http://russetlodgeknits.blogspot.com/

Yours truly has helped guide her in developing a pattern for these historic reproductions. No pictures are posted on the website yet, but a prototype bonnet is on its way to me, and I will post a review when I receive it. So, interested parties might want to wait for that before placing an order. But, I'm in no doubt these are going to be fine bonnets, Diane being the experienced knitter that she is...!