try one on, if you think it's ok wear it, I have seen many scots wear matching ties and bow-ties.
some of the kilt nazis round here may tell you it's not ok..but I make all the rules now and I say it's ok.
the only one I didn't like was a bright blue and yellow kilt with a matching tie,bit hard on the eyes, I think black watch or some other dark or not too bright tartan would look ok with a matching tie, even royal stewart looks ok with a tie.