Well, it has been quite a journey. Thank you Clubmkan, but those holes are dry, unfortunately.
Heasmans have been very helpful - shoutout to Jamie

- and between reading the faded stickers on the shocks and his info we have
Bilstein PSS9
Front: F4-BM5-6415-H0
Rear: F4-BM5-6416-H1
Bottom bush (F&R): E4-GV2-Z018A00
An interesting and possibly troublesome feature is that not only is the rubber bonded to the central tube for the mounting bolt, there is an outer metal sleeve as well, sitting immediately inside the eye. Removal of the old bushes (only 20+ years old) might get interesting
I also have the tech drawing with measurements which Jamie supplied, and the end result is that none of the bushes current found on the interwebs, none of the poly bush people here, in the USA, UK or Europe make a replacement, or stock a bush which is immediately useable or even nearly. As I sourced a set (No2, now on-sold) from Shox.com in the US, I decided to roll the dice one more time and sent a query to Bilstein USA around lunchtime today.
About 7pm I get a response - from the Mothership no less, a helpful email from Katrin K who tells me, yes, they are not in the catalogue, not in the database accessible to distributors, but hey, I think someone here has some in their bottom drawer, and if your distributor asks nicely, well who knows what good things may happen ... or something along those lines. An email will be waiting for Jamie on Monday morning asking Heasmans to followup and get back to me. Hopefully the pricetag will not be too exorbitant ...
If it is, I have one more roll of the dice up my sleeve. I think that bushes for leaf springs may be useable, but not as found, and I really don't want to start cutting poly, and machining adapters, unless absolutely necessary.
