Thanks for the replies. So, for the coat (since I seem to be on the right track with the waistcoat) I am trying to find a workable length of cut-away and tail so that the kilt is not interfered with.

I found the following image.



This looks a bit informal though not necessarily the stuff of balls.

Do you think it would be better to go with the closed single or double breasted jacket? or to spring off the image of the fellow in a tartan jacket that JSFMACLJR posted and cut it so the jacket falls open in front?