Hi Gerard,
I recently found my speaker were not working, and got these:
https://www.ebay.co.uk/itm/192155227089They work great with my period Pioneer radio/cassette unit.
They fit ok in the proper position, not in the doors but in the space above
the footwell pockets. Wiring is all there on both sides, and you'll find, if you haven't already,
the radio plug behind the radio slot. Also there is a 2 way connector for an electric aerial,
wiring also in the boot, left-hand side.
These speakers are very slightly too big, so I made a couple of 6mm spacers to let them stand off the bodywork.
Hope this helps, N.