Looks like you could get the betaflight f3 in there, it has a pdb and 4 in one esc.
I have to tell you though, it looks tight. Frsky has a receiver about the size of a thumb nail that would defiantly work. Getting a 25mw or 200mw small enough would not be hard to find either.
My personal opinion, much less of a hassle and significantly cheaper to buy a Eachine Wizard. They fly great and hold up well in crashes as well as having a lot more room for mounting stuff. Could buy one ARF for the cost of what you will pay for the components on this build unless you already have the motors. Not much of a problem to upgrade them to 4s either. Then they scream.
