That's a nice headstamp sandgroper. I see you're in Australia, I'm just working on putting up Eley and Kynoch headstamps which I'm sure you've found a few of. Getting dates for them all may take a while though.
I have assembled a very large collection of headstamps over the past couple of years. Love to find them here in Tennessee. I presently have over 100 different in manufacturers and varieties. Here is a picture of some of my favorites (Indians and Chiefs). They display well in the Gem boxes.