The middle piece is a CF JDM legacy rear diffuser (Didn't have a company name from the online store I purchased it from, they pop up on ebay here and there). It wasn't made for the USDM models so it is not a direct fit, but I used 3M tape and 2 small metal clamp pieces to keep it tightly in place. The rear canards belong to an RX-7 rear diffuser that I sourced.
A lot of guessing if the parts would match the contours of the car and measuring/adjusting, but I'm very happy with the way it came out, particularly the canards.