I purchased this at a local militaria fair here in Australia. The person who sold me this group of items had discovered them in his grandfathers shed when clearing it, out the explanation given to him at the time was that it came from a relative who was a pilot in WW1. I dont break up items when they come together as this grouping has.
The Grouping consists of a heavily quilted padded coat made from canvas and green uniform material, the buckles are very unusual and interesting and were obviously designed to take a lot of wear. The interior is ink stamp marked Q W^D 272 (could this be Queensland) and there is a makers label also marked but is nearly impossible to read. It comes with a WW1 period leather flying helmet with a makers label inside, the leather is in good condition but a strap needs to be re-stitched to the front as shown in the images. There is also a set of pilot goggles that came with the group that has a cracked lens and the elastic needs re-stitching.
I have never seen this pattern of jacket in my entire dealing life and beleive it is certainly a rarity. Wether it was made for pilots or despatch riders I dont know however both used any weather proof coat that they could lay their hands on. Also both used leather helmets and goggles.