On Monday, April 22, 2013 4:50:37 PM UTC-7, Karl Townsend wrote:
I'm on a snipe hunt for a special compression spring. it needs to be

conical with the large end OD around 0.390" or a bit smaller (like

3/8) and a small end OD of 1/4" or a bit smaller. When the spring is

compressed to 0.225" high it needs to push 8 - 10 lbs. force.

Well, the stainless springs in Delta faucet seal kits are about that size.
They're a bit light on the force side, though.

You can often stack Belleville washers (adding them in parallel for
higher force, or in series for lower) to get a
target stiffness. They're conical, but not as extreme as your
description (nearly flat disks).
Four McMaster-Carr 9712K58 in series would be about right.