I see a few 1400 rated hunters running around with Season 4 weapons and whatnot.
(Eg. http://armory.warmane.com/character/...utland/summary)
The addon Atlasloot is telling me they should require 2050 PR.
A quick search and relevant wowhead comments also tell me the same (http://www.wowhead.com/item=35110/br...araxe#comments),
noting that while Season 3 weps did not require any PR, this was changed for the S4 weapons.