It seems like it should be possible, especially with the availability of high efficiency GaN LEDs. The peak sensitivity of most alternative process materials is in the 350nm range, but the sensitivity is broad, extending well into the blue. GaN LEDs also have a broad spectrum, which makes them a good match for the application. I would guess that the 375nm peak variety would be the best choice. There are a couple of cautions. First, LED brightness can vary quite a lot from one lamp to another when driven at the same current. You can trim the brightness by trimming the current, however. Also, not all GaN LEDs offer high efficiency. You can shop, however, comparing the outputs at a given current.