We have solved Welshys problem. He need the 2594039. The 84034 is for the double slipper.
For others that have problem finding parts, try
http://www.modellbau-seidel.de
They have most parts in stock like suspension arms, alu hubs, damper towers, uprights, outdrives, pulleys, drive belts etc.
I´ve purchased parts there several times. Cheap and fast shipping.