Australian made Vintage oil pump restoration Gilbert and Barker Gilbarko

Here i got a vintage oil/fuel pump to get working again.
it's made by
Gilbert and Barker here in Australia who trade under the name of
Gilbarko
Not sure on the actual age, but i suspect it is at the "newest" 1950's as per the internals are all cast iron with a brass ring as a sealing ring, which was phased out as far as i know before the 1960's
Anyone with more information, i'll be glad to hear :D