The good thing is that these are like bum holes, they are everywhere and everyone has one. To work out the breed and age you will need to contact Don Reid of Vintage Spares on the Gold Coast by phone or snail mail only, he has the records. Other Members here might have some details as well. Look for a serial number on the end of the crankshaft.
These are not a carby they are a basic fuel mixer that has a needle inside a taper and you open that up by screwing the knob on top.
Boycott got through on your topic but not in your thread, lol.