Well the 1250 should work as long as you're on a code of 4.2 or later.
But since you are asking about a "N-K9" which I understand to be a non-fcc AP, I'm not really sure how that works. So the real question here is, what is the different inregards to registering with controllers when it comes to FCC,ETSI,Korea,etc.. configurations
The following new features are available in WCS 188.8.131.52
802.11n support-The introduction of the Cisco Aironet 1250 series access point, a business-class access point based on the IEEE 802.11n draft 2.0 standard. The access point offers combined data rates of up to 600 Mbps to meet bandwidth requirements. Cisco WCS display screens include a listing for configuring, managing, and monitoring 802.11n access points and their associated wireless LAN controllers.
Have a look at these two threads that detail the upgrade of the 1252 from Autonomous to LWAPP to work with the WLC. There are some very helpful tips from Scott and Jerome;
Transferring Crash file from standby: Login to the Active WLC in HA.
From CLI: (Cisco Controller) >transfer upload datatype crash (Cisco
Controller) >transfer upload filename (Cisco
Controller) >transfer upload mode tftp (Cisco Controller) >transfer
This is the start of a display filter cross reference between Wireshark
and OmniPeek. The 1st installment is a table of advanced filters. More
filters will be added as time allows. It is a living doc, so check back
for changes every so often Please feel f...