I ordered springs from Wolff yesterday. Online order with confirmation ... seemed easy. Don't have them yet, of course.
From their web site ...
HAMMER SPRINGS
For use in:
P225, P226, P228 and P229
P220 with serial numbers above 219166.
Reduced Power...: 16, 17, 18, 19, 20 and 22 Lb.
Factory Standard.: 24 Lb.
Extra Power.........: 26 and 28 Lb.
Stock No. 283xx - each.....$ 4.29
Stock No. 284xx - pak of 3 (1 rating).......$ 8.99
Stock No. 285xx - pak of 10 (1 rating).....$19.99
Please Note: Replace the "xx" in the stock numbers with the pound rating of spring.
HAMMER SPRING PAK - reduced power.
This pak contains 1 each of 16, 17, 18 and 19 pound reduced power hammer springs above, allowing adjustment of the firearm to individual requirements.
Stock No. 26575.....$ 10.80