Hello there Geoalex, and welcome to the forum. You'll find we have a multinational membership here all very helpful and happy to look at and chat about any pics you care to post. As luck would have it, I am only two hours down the road from you, mate. I do need to get back to Craig yet from his post above, but very happy to give you a complete rundown of your rifle and a brief history of the Lithgow snipers too.
Rifle No 28046 was completed and sent to store on 5/4/45, one of 12 finished that day. Thats about all I can tell you from the serial number, sadly.
To give you as complete info as possible I will need some information off your rifle. If you'd rather not post details here, I can email you the questions. I will not divulge any direct info you give in this way, or tell anyoine the locations of specific rifles. I have details of over 200 rifles in my survey, so am well positioned to make comment.
Look forward to hearing from you again, mate.
Regards,
Brad.