The rear doors look like one of the 2 "regular" Subaru 3-hole configurations (not including the "new" BRZ/FR-S configuration, which is Toyota/Scion-derived). If you measure the triangle I can confirm it with a stock speaker or existing adapter template that I have.
In the front, that is PROBABLY a fairly standard 6x9" shape and mounting configuration, but the 4 holes might have proprietary locations. Measuring the rectangular hole configuration will help with determining that.
If someone is willing to pull a stock speaker and send it to me I'll be happy to send you some 6x9" to 6.5" adapters to try out. Of course, I'll send you back your stock speaker as well.
Front door connectors look like they need the Metra 72-8104 (see picture here: Wiring | Subaru Audio
). I can;t see the rear connector but I'd bet that they are the same. If you can post a shot of the connection point I can confirm.
In the dash, that looks like the same physical mounting pattern as the BRZ/FR-S and the '12+ Impreza, but the speakers are different and the connectors look new.
I don't really recognize those dash harnesses from any past Subaru. May be a Toyota or Nissan connector- I'd guess Toyota if I was placing a bet on it.
I will try to call Metra and see what they know. I don't actually DEAL their products but I was somehow made a Metra dealer after calling them up to ask for product info. I can access their dealer tech support- maybe someone there knows something.
Not likely, as they are still far behind on the '13 BRZ/FR-S wiring, but it won't hurt to ask.