Hello,
I'm sorry but my google translate does not seem to like Hungarian.
Regarding the Joffre-
A local club
(The Model Steamer Club - Glasgow ) Had as one of it's members a Mr Philip Thomas. He was, as far as i believe, the Draughtsman behind the Joffre as produced by Caldercraft.
Regarding the plans a call to Jotika might be in order - I'm aware that duplicate plans become available from time to time on ebay ... whether they should be there is beyond my expertise. I believe a legitimate set of plans is available via one of the main model boat magazines.
One thing is for sure as a model for a steam plant at a larger scale is a real possibility as i have seen build threads on other forums over the years.
I'm sure the steam enthusiasts amongst us would like to see your build take shape.
regards,
Kim