My buddy (11C ABN) is shipping me a MKE SP89 take off barrel for my mockup and the handguard has been ordered from HKPARTS.
I think I can make the SP89 barrel work with a 22mm AK74 trunnion.
My "K" mockup is starting to resemble this a little. I'll use HK sights though. I also contacted SAMSON MFG. about a handguard that might work very well for this application. http://www.mountsplus.com/AR-15_Acce...STAR-MP5K.html
I'll have to wait to hear back from them and see if it might work or not.