Who makes these pendent lights? Model number? Thank you.

They sell can to pendant conversions. I got mine from Ballard Designs. You remove the trim piece and screw it into the socket. Adjust the cord length and tighten the plate against the ceiling. I think it was maybe 5 mins to install them. Here is a link to one of them but they have all different shade choices. https://www.ballarddesigns.com/can-light-adapter-glass-bell-pendant/lighting/all-lighting/426819

Yes, where you see the bulb hanging down in the nook is what I'm shopping for. I'm thinking a diameter between 15-20" for a light over the table. The table that will be going there will likely be rectangle measuring somewhere around 34-36"x42" A chair on each end of the table.

Although you certainly have room for four, I think that odd numbers look best. I would hang three of them but I think you might want bigger ones than the size you've found. I've been looking a lanterns for a small vestibule and everything I look at is way too big, so you shouldn't have a hard time finding larger ones. Circa Lighing has a lot of lanterns that seem like the style you are after. Looks like you will have a stunning hallway! Love the arch and long lantern view.