I imagine he'll be wearing a dress shirt with the kilt, so yeah, he'll still need cufflinks.
Have a look in your local card shops, you sometimes find things at their tills, good luck charms, something small enough to slip into his pocket, he knows it's there, but no one else, just your wee secret.
I know my husband bought me some stones, they're smooth with the words love luck and happiness I think, and they're in a little pouch that I can slip into my pocket if I feel I need a bit of support. Or maybe that's a wee bit girlie