This is a late model GM fuel pressure regulator that was used on the BBC TBIs, PN 17113079, and has since been discontinued. The regulator delivers ~ 28-32 PSI and is fully compatible with the earlier TBI injector pods. The unit includes all that is shown in the photo below, but does not have a regulator diaphram or gaskets. These can be ordered from most local autoparts stores.

Price: $55 + S/H