Tiny Clanger

Yes — after all, how else can you grab a friend's unattended machine and change Alfred to use 36pt pink Comic Sans? 

I've created a new theme, and edited it to my liking… except for the font.
 
I don't like any of the choices Alfred is offering, and can't find how to bring up the standard OS X font selector to choose the one I do want.
 
Is this actually possible? I realise it makes the theme non-portable to have a font that's not on everyone's system, but I'm designing this theme for use on my computer, so I don't really care all that much