You can have more, but I recommend sticking as close to 40 cards as possible while aiming for a ratio of 24 playable cards to 16 lands, adjusting for your curve as you see fit
Youll probably want to have a Rule 0 discussion about running this commander because some players arent a big fan of their opponent playing with their cards
All that said, lets look at the reprint value here
Excalibur CCG Plus Sleeves (63.588 mm) firmer grip, slightly tighter fit, perfect for double sleeving and storing in binders
9 Misaligned Holos Slightly Shifted Much like the miscut cards, misaligned holographic cards occur when the holographic foil is moved slightly during printing, creating a 3D or cut-out effect, such as on the Fossil Articuno card pictured
It could theoretically appear on an Instant or Sorcery, but we have yet to see that occur and how specifically that would work