The Spey was developed into the Tay which was fitted to the B727s of UPS on the 1990s.
The Fanned Spey, as it was called in the early 1970s, was to be fitted to the BAC1-11-700 but never got off the drawing board.
I don't think a re-engine program for the Trident 3 would have got far as there were structural problems with the wing that limited their life.