sturmey archer is not going to have a disc brake hub, nor will you probably find 1" threaded forks with disc brake mounts, you could try 1" threadless forks but they will most likely be suspension. is there a good reason you would like disc brakes? a bike like that should never need them. if its a quality thing, good rim brakes will be just as good. also, i'm making a guess here but i think a disc brake on the front without suspension forks will throw you end over!