I'm between a 36 and a 38, too. I have the FSA Compact Wing Pros in a 38, but prefer my narrower Deda 4 Girls. They're also a 38, but Deda measures outside to outside, rather than center to center.

I had trouble finding the Dedas new and ending up buying them on TE used. You might check out eBay if you decide to go that route. Other brands/styles I considered were the Salsa Poco and Salsa Short and Shallow, and the Biomax. The Dedas, however, were about as narrow as I found.