Last year I saw a few listed around the $900 mark. Right now, Bullseye is the only place that I have seen them for awhile. They used to sell around the same price as the regular shadows, but given they are hard to find these days, everything has gone up in price and Bullseye is usually competitive, 1K+ is probably pretty reasonable.
I can't comment first hand on the difference in performance, but have been told it is more difficult to tune a trigger with a decocker. If you don't care about the decocker, the Shadow for less money would likely be the (marginally?) better gun. I like decockers too though so if I was in your position (and had no plans on competing), I'd have no issues springing for the Tactical.
to add, looks like P&D has a Tactical as well