With the MacKay tartan, USAK's lovat green and lovat blue hose would work well. They would complement the darker colors of the tartan, but provide a little contrast.

Most bottle green and navy blue hose are quite dark, and would give a similar look to your black hose. The Lewis hose have brighter bottle green of which I'm very fond.

I'm trying to suggest that you not limit yourself to black and white! It's my firm belief that lovat green goes with everything, at least for day wear.