Welcome to the forum.
Nice old HP. You should post it in the Ultimate HP thread in the 1961 - 1980 section. There fifty something pages about HPs. I posted pics of my S1113xx last night.
The 29133 numbers should be assembly numbers. If you take the cylinder off does the crane have the serial number stamped on the inside next to where the cylinder would be when it's on? Mine does and just wondering if they stamped all these early HPs there.