Here's another thought to add to already excellent suggestions of Jock, Matt, and now Rocky- what about a sweater vest? I have 2 Argyle and one plain black one that I wear to spruce myself up. They look great with a collared shirt and tie, and are a good length to wear with a kilt. Or you can go to these guys http://www.newjerseypiper.com/vests.html and get a nice 5 button waist coat for about $35.