Looks like 7 left as I type. People are paying a lot more for these as service parts to get "Reaktiv" type on their bikes.
Having ridden same Treks with and without these I can't say enough how good they are. Imagine the firm of some linkage designs when you pedal without pedaling hard turning most of your suspension off. Imagine the traction of a Horst-link without your bike wallowing into most of your travel gone and pedal banging.
The 2016 EVOL version is indeed better - no clicks, more simple design, but $500. Some of the early "Reaktiv" had a clunk problem Fox fixed with different oil.
http://www.ebay.com/itm/361378535790?_trksid=p2060353.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT