You're not going to find any significant discounting going on as you see with guns, so brace yourself. Optics Plant has good pricing, but I can't say they are the lowest.
I lucked out and got mine slightly used on eBay for just under $300. The guy had mounted it on the gun, and that was it... it had no signs of rough usage (as it does now!).
The problem with solid stuff like Aimpoint and EOTech is that they are in demand because they work.