I would start looking in this order: TVLogic, Wohler, Flanders Scientific, Sony, Panasonic, Marshall, SmallHD, Ikegami, Blackmagic Design, Atomos, Lilliput, Feelworld, and JVC.
I understand the first three (TVLogic, Wohler, and Flanders) specifically might be out of your budget, but I threw those in to give you an idea of what some of the top end brands are to provide some context on pricing/cost.
So you'll probably want to start with Sony and work your way from there.
I would personally try to stick with the main broadcast brands if at all possible. That will be the first 8 in the list.
Hope this helps!