Hi Cheers - I'm still trying to understand a few terms. The 14 x 12 bodies - are they the "National Standard Deep"?
No, they are simply National Standard extra deeps. Also called Jumbo or 14 x 12.
National hives have three different sized boxes - shallow deep and extra deep. What could be simpler than that? Boxes can be used either as brood boxes or honey boxes (commonly called ‘supers’ when used for that purpose - but there are lots of non-thinking beeks that refer to any shallow as a ‘super’!)
Look at the frame designators - ‘S’ refers to ‘shallow’, ‘D’ refers to ‘deep’ and the 14 x 12 is the extra deep (but gets called all sorts of names!).
I would start either with 14 x 12 Nationals or Langstroth, but most likely the former.
Do take some claims of their bees needing multiple brood chambers with a pinch of salt - the queen has a finite maximum laying rate (and usually peaks early in the season). Each frame has a fixed number of cells and the brood cycle time is around 25 days (worker brood plus recycling the cell for its next cycle).
Even at 3000 eggs per day, that means that only about 75,000 brooding cells are required for a short period each year. If that lay rate were maintained and the workers survived for 7 weeks, one could calculate the terminal colony size quite easily. Do that and you will realise that some simply exaggerate!