If there's not one in the showcase, and you haven't gotten any action here - let's face it, we're not that large a group of regular participants - I would start beating the bushes in the usual spots - Reverb, eBay, etc. And at some point, for what you're after, it seems like you'll need to make a choice between waiting around some more, or just ordering the part you want. Scalloped fretboards don't come up that often in the secondary market, especially on the conversion-scale neck.
Best of luck.