Some of us got a kit with out bikes (I did in 08) that included what looks exactly like a Baja Designs tail light. Looks like this.. http://gallery.me.com/glangston1#100024/IMG_6450 Not sure if you can buy it separate but I'm pretty sure there's something similar out there.
I am using one from sicassracing.com on my 450 it's the Edge2 LED underfender Part #: 21-221 fits nice
I'm using a Whelen LED (made for emergency vehicles) with a Baja Designs drop down on both my Huskies, super bright and super tough. http://www.strobesnmore.com/whelen-tir3-super-leds.html https://www.bajadesigns.com/NET/P-602022/Taillight, Bd Led Dropdown Support Only
The tail light in the '08 p/u kit is a UFO light, it even has DOT markings on it. Looks like the UFO Phantom available here. http://www.oemcycle.com/Item/product/5186/ I have not seen one in person, but I don't think the EDGE tail lights say DOT on them.