Hi Dan,
yes, dimensional drawings are almost impossible to find. I tried that too.
But these pumps exist in any size. So I decided to take a figure and an engine
as a proportion. So don't worry about sizes!

Hi Craig,
yes the guy is an LGB engineer who quit his job on the steam engine, a dangerous
job where you can easily loose an arm in an accident!

That's what our hobby is all about: sharing ideas.
Isn't that great. I am glad my work gave you an inspiration.
Thanks for the comments.
Stefan