As I recall, 1987 was the 1st year for TBI, perhaps parts could be canablized. Pump in tank(s), I believe the fuel pressure spec is 9 to 13 psi.
This is correct. The spec is 9-13psi.
The sending unit with the integrated pump and return line is larger on the fuel injected truck, so it won't fit directly into the older tanks. The 87 used the same tank shape as your 86, but with the larger hole for the fuel injection sender.
The combination of a new spectra premium tank and a sender/fuel pump combo is under $200 from rockauto. I am not sure you could set anything else up for that price (other than a junkyard raid).