Pitons are often misleadingly difficult to determine their age due to deterioration insitu, and the best estimates of their antiquity rely on their make and design, as well as the surrounding circumstances of where they are found.
At Buffalo the early lines that have pitons or the remnants of pitons left in them, pre-date easy availability of Chouinard types and also to an extent the earlier Clog types, and although Clog were used occasionally they weren’t commonly left due to their cost and difficulty in procuring them in those days.
The oldest stuff is often of home made backyard origin and later when pitons were more widely available/used, Stubai was the manufacturer of choice due ease of procurement and reasonable price, eg most of what’s left of the Ewbank / Baxter / Dewhirst / Gledhill stuff around Ozymandias area, is Stubai in origin and dating from the late 1960’s.
Incidentally the first major line on Buffalo north wall to go was Emperor in 1966 and used homemade ‘pegs’ made by Reg Williams if I recall history correctly. By comparison Chouinard pitons started manufacture in the late ‘50s but were like hens teeth to obtain in Australia for a very long time.
The main usage difference between Stubai, Clog, and Chouinard pitons in terms of antiquity is the hardness / malleability of them. The softer malleable types were more often left insitu due deforming and the hardened steel Chouinard pitons were capable of reuse. This lightened ones rack considerably, but also resulted in few being left.
These days providence is blurred further because of the second hand market providing ‘old’ stuff for modern use, with even Chouinard pitons now being regarded as old technology.
With this in mind I’m aware of relatively recent ‘canyoning’ trips (amongst other exploits), conducted about four years ago by another of our inmates, DMWdesign and his associates, which included Mt Buffalo, and the gear they used included second hand pitons.
Commercial operators and outdoor education groups have also likely left legacy of their passage too.
The fact that what you found has 4mm chainlinks attached, presumably of the split type(?), indicates a more recent expedition to my mind.