When I enquired from Speedseals if they could supply for my mini-14, they said to send the engine number and they would know - apparently some of the pumps were produced in-house by Sole and the standard fitments don't work. You might try asking Sole and/or Speedseals?
The Sole UK distributer is I think called Diamond something, somewhere in Yorkshire.Varne27 mojo knows of them. They may be able to help.My mini 14 appears to have a Sole manufactured raw water pump.
Maybe someone knows of a parts supplier in the south/south east?
Yes, diamond Diesels www.diamonddiesels.co.uk. Otherwise there is www.solediesel.com. They offer manuals for discontinued models as downloadable pdf files. I couldn't see a mini-26, though.
Rob.