I am selling a set of Prodrive '05+ STi springs, the red ones. I loved these springs but replaced them with stock '05 STi springs for a bit softer ride and a little more ride height in the front. They should be an awesome match for OEM STi struts. I ran them on '07 FXT over WRX struts with Koni inserts.
The red Prodrives are advertised as being 25% stiffer than stock USDM STi springs. They even out the stock STi stance, lowering the front a bit. The springs have some usual scratches on them, otherwise they are great.
$200 + shipping.