Lessing,
I designed the MicroStars and make the clustered LED's sold by Berkeley Point. At the time I designed the original MicroStar, I was looking for a small LED with good even beam density. Of all of the Nichia white LED's, the 312 gave the best beam for my needs. The die is the same in all of the white Nichia's, regardless of 3mm or 5mm package.
There is no 5 mm version and no, the lights are not currently UL listed. My previous employer, Suncor Stainless, who makes the MicroStar, looked into the UL listing but I believe the process got bogged down and eventually shelved. I don't recall the terminology but since these LED lights aren't a complete unit; considered a component, there is a UL consideration but I don't think they qualify for the typical UL approval.
I vaguely recall that since these LED lights have a combined low voltage and current, they fall below some threshold or level where UL is deemed manditory.
- Don