You can get a UV for a few bucks (>400nm wavelength), but the emitter cost alone for the Nichia 365mn is $100 or so. Cree has higher power UV emitters than the Nichias, but are 395nm, which should work just fine for most applications. Nailbender has these available for P60 drop in's, as well as the Nichia's.
So, a premier setup would be the Nichia UV P60 drop in from nailbender ($130?) + a decent quality host like a Solarforce for $30.
I use the nailbender drop in with a LM (single RCR123 battery), and as far as LED UV goes, it is terrific.
John F