That looks like the Subaru Brat body but it is not the Subaru Brat chassis. The Subaru had a monocoque chassis in grey (could have been dyed). The front and rear supension are completely different and so is the gearbox and other minor details.
I dont know enough about the original Blackfoot etc but it certainly is Tamiya, may even be a melding of kits, custom modified jobby.