Value is often subjective, and condition, age, etc. will adjust it, plus just finding the right buyer. Specs on the bow also seem to make a difference. Something in the 50-60# range seems to sell easiest. I do know of a High Sierra that sold recently to a friend and I believe the price was $475 with one set of limbs. The second set will add to the value of the deal, but again, the specs on them will make some difference. I have one that I haven't listed yet, but if I do was thinking somewhere around the $500 mark would be about right. (Although mine is newer than the one you are looking at)
Without going to the Fox website, I would guess you are probably looking at somewhere around $1,200 or more in new value there. Most bow deals seem to be anywhere from 50-70% of new, with some exceptions on either side of that.