Accuracy international AE First generation

Jagger

Private
Minuteman
Dec 17, 2021
3
0
Florida
I just picked up a accuracy international AE MK1, it has a plain non threaded barrel. Can anyone point me in the direction of a website that sells threaded barrels for the AE MK1? Also can anyone shed some light as to if the MKII or MKIII barrels are compatible with the first gen.

Any help is much appreciated.