After posting I did some looking and found their application site:

http://www.garenfest.com/artistapp.htm

Are these prices typical for space at Ren Fests?

I noticed one other person who I think had on a black UK as you describe mixed with the more traditional garb. I saw so many guys walking around in baggy OD cargo shorts and was thinking how logical of a next step the Cargo kilts from UK, FK, AK or PK are. Oh if they only knew what they were missing