Are there any manufacturers of the correct seat springs for a Terry seat?

I need a full set for 1 seat and a set of front springs only for another. I'm sure I saw a recommendation a while ago but no amount of searching will find the details!

email (option): r1155n@gmail.com@

There are sometimes sets of cheap crap Asian springs on ebay. But I've bought quality springs off this guy.
https://www.ebay.co.uk/itm/183492104769

Ron

email (option): ronpier@talk21.com

Thanks Ron!

email (option): r1155n@gmail.com@