Unless you can find one used, around $400 is what you'll see (get the DL if your going to overlay film). Be careful if you use their proprietary L7+ GSXR1000 fork stem mount. My AS 2 DL flew out under HARD late braking on a some-what smooth track (even super tight in the stem) and thankfully the DL is tethered by the data cable or else there went $700. I use a cheap METAL bushing (instead of the rubber one that comes with AS 2's mount kit) that comes with a Chinese RAM mount 1in ball (ebay).
Superbike unlimited has them on sale. https://www.superbikeunlimited.com/index.php?route=product/search&search=solo&category_id=0 Solo 2 $351.12 Solo 2 DL $615.12