Cheap option can be to find one of the cheap 4AA powered fluorescent lanterns (the one using a 4W linear tube), and simply replace the tube with a BLB version. This is a quick and easy way to get a pretty large amount of UV (~360nM). Cost for this for me to get would be as follows:
Lantern: £4.99
F4BLB tube: £4.99 and a set of batteries. Only actual modification I tend to do to the lantern itself is the removal of the plastic lens, as it cuts out a fair amount of the UV emission. It is however a flood, so I'm not sure how appropriate this would be for your application.