Check eBay, LKQ and any online salvage/recycler. You can also ask in the main digital cluster thread stickied to the top of this forum, I believe the OP of that thread sells equipment.
Found mine from a salvaged Stang at LKQ Online ($150), had the firmware flashed from Automatic to Manual and the zeroed out the mileage. Installed, increase mileage to current, some additional Forscan programming done. Did the whole update around 500-600 bucks. They can be found on LKQ, Part Farm etc.. but takes some digging. The firmware can also change it from MPH to KPH.