I own three of these kilts and they get quite a bit of use. These fit at your jeans/pants waist so I wear a 36-38 and take a Large in the kilt. This past year the one I bought was a little snugger, due to manufacturing not extra pounds, that the other two I have. From your post I would say a medium would be a good fit. Good luckl finding one, Ill explain.

All outdoor gear, especially clothing, is seasonal. This means the ElKommando kilts you see left on sites are from last spring. They have bought at a winter buying show for this coming sping sales. Retail stores only buy what they feel they can sell and manufacturing companies such as Mountain Hardwear only make what they think they will sell. When you get to the end of the season there are no more because they dont keep making them through the year. You may luck into finding a medium on Moosejaw, Mountaingear, REI or other site but I doubt it. Your best bet is to wait until spring and jump on one when it comes on the market. These have been popular enough for them to keep making them. REI sells out pretty quick but some of the web only outlets will have them longer. It is a game played by manufacturing and retail and it is a pain, I used to own an outdoor retail store, so you just hope as a consumer you will find what you are looking for. After the season your odds get slimmer and slimmer. Best of luck, the Elkommando is a great kilt to have for hiking, running, gardening, yard work.. or anythying.