Prius 5 Head Unit/Display in Prius 2

Hello everyone! I have a 2012 Prius 2 and am looking to upgrade the head unit. I was looking at Best Buy but I am now thinking of getting a used head unit from the higher-trim Prius 5 of the same year(s) with navigation and whatnot. I know it will fit in the spot but I am concerned it won’t hook up to things like the speakers because the head unit is designed for JBL speakers and I have the base generic speakers. I have seen that the place where you plug in the speakers to the head unit is different with JBL on a prius. Additionally, will I be able to purchase a backup camera and just plug and play?

I am also looking into those “Magic Box” devices that plug in to the head unit and give it Apple CarPlay. Has anyone tried this on a gen 3? I found a YouTube video of someone successfully using one on a gen 2.