I have a set of headlight ears for a K5... chrome style with the bracket for beeper mounting. I'd sell them for $20 plus shipping, but shipping to Australia will likely be $25-30 assuming I can do it by first class International. I may have a decent grab rail also that I'd sell for $15. If I could get them in the same package and the weight is under 4 pounds, shipping would stay in the $25-30 range.
I'll have to look closer at my grab rails and get pictures posted if the price doesn't scare you away. I have 2-3 grab rails, but at least one has some twisting of the turn signal mounts.... I don't remember for sure about the others.
The headlight ears are decent structurally, but do have some rust that won't likely clean up, especially on the insides and at the bottom of the ears. I cleaned the outsides a bit with chrome to show that they will clean up some, but not completely. I'm guessing that if I put them on a buffer wheel I could get rid of all the rust on the outsides, but not the insides. These are actually good candidates for painting, but could be decent if you left them chrome... see the pictures for a better idea of their condition.
http://s590.photobucket.com/user/ganelson/library/1975 CB750 Headlight Mounting Ears?sort=3&page=1