The Academy M163 latest boxing comes with both indi-link plastic and vinyl track options, PE for the engine screens and a few other parts, and all the sprues out of their M113A3 kit for better detailed parts. Definitely the kit to get.
Depending on how detailed you want it, get the Hobby Link M163 interior. It has parts for both the late or early version. Ealy version shown below.
Available in the US at Wanamaker Hobbies: https://www.wanamakerhobbies.com/
Not really. It is buildable and looks like an M901 ITOW, but it’s not great. More info on the Italei M901 ITOW here:
M901, take 2 - Armor/AFV / Modern - KitMaker Network
Also, I have built a couple M901 ITOWs and a bunch of M981A2 FIST-Vs. I find the turret size just fine; they look correct. I served on M981A2s and it looks the same to me. The turret was small and the hatch opening tight, and I am not a big guy (5’ 8", 155ish #s as a 2LT on them). I would forgo the PSM set and go with the kit parts.