I had a smaller clamp light w/ reflector that the bulb actually fit into, but it was so shallow that only the base of the bulb (not the actual light) was in the dome and the spiral light extended beyond it ... all that light was escaping out in all directions, a very small portion hitting the plants. And of course it is very blinding.
Then I bought a bigger clamp light with a deeper, wider dome/reflector -- this is the one I referred to in the initial post -- but the reflector tapered off too quickly near the base and the bulb would not screw in all the way before hitting the reflector.
The standard clamp fixtures at most hardware stores are for relatively high wattage bulbs ... the smaller one goes up to 150 watts; the larger one is 300 watts. Pikevi -- Take the bulbs with you to your hardware store and try to fit them in the clamp lights -- I bet they fit one of the several sizes. But they will stick way out beyond the reflector. I'll probably breakdown and buy the $47 (incl. shipping) one on the internet designed for the 85W bulb; here is the link:
85 or 105 Watt Reflector
I've wrapped aluminum foil around the small clamp light reflector to reflect more of the light, but this is very temporary (because very ugly).
Please keep suggesting. Thanks.