87/91 Help Please
 

I came across an 87 rx7 that has a 91 jdm 13btt swap in it. the car has around 62k and the engine about 1k miles, the problem is he has an aftermarket fuel pump (walbro i think) in an effort to satiate the twin turbos, and it has quickly worn the injectors *still 550cc.* As a result, the engine consistantly wants to flood. Now what i am looking for that i can not find at all, would be 4 550cc stock injectors, and a fuel pump regulator to keep the fuel from flooding the engine. Can anyone help inform me of where to find this fuel regulator? i've searched atleast 5 rx7 parts sites.
Thanks