Re: I've perfected the sprung saddle!!
Like you, I need a softer ride than most bicycle saddles provide. I've had good luck with using automotive valve springs on three seats that I've built. They seem to offer more 'spring' than the ones that I find on bike seats. And, they're cheap. Most engine rebuilders throw old springs in the trash and they will happily give them to you if you ask.
They won't be chrome plated but can be cleaned and painted.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"