You can get optics direct from Fraen, however I believe there's a minumum order. Also they are an Italian company and as such uses the Euro as monetary units.
You could always give Future a call and check.. However, I will ask my contact if they are available from Future yet, and post what I find out. Fraen is just now hitting the market with optics that are taylored to flashlight use.
I just received some "ring spacers" last night to move forward on my evaluation of the Lambertian optics. The ring spacers permit proper use of the optics without the bulky holder.. I will be doing a complete write-up soon. I did a quick test last night and the results were encouraging.