I did ask Mulfab about the 4 leaf 4 seat springs, but I'd ordered, recieved and fitted the BCC before they replied to my email. They did still supply them.
Many thanks.
BCC look like the go-to people now.
Paul Costock, UK Plus Four 75th - Furka Rouge - Pip Disco 5 Teddy - 17h1 Irish Draught cross