The description of the forks by the seller of the Showas is inaccurate. He lists them as "THESE ARE THE HARD TO FIND OEM DUCATI THAT EVERYONE REPLACES WITH ON THE MONSTER AND SS AND SPROT 1000 MODELS, AS WELL AS THE PAUL SMART ETC".
Monsters/ST models have a different length than the SS models, considerably so. The SS forks are longer and can be mounted to SC's, but they'll stick up through the upper clamp and are not as desireable (unless you want to attach clip-on's above the upper triple clamp). The price is probably OK for Monster/ST models, but too high for SS models. I'd want to know the length before making an offer.
The Ohlins units are the same ones that were previously listed for $2499 and got no bids. Looks like they'll go for a more market-correct price...