I looked and didn't see any either...........check Ebay, I remember seeing some there in the past. Where do you live, maybe I'll sell you mine (kidding).
Regarding the new Gavita's- I also see they use 800 watts vs. 645 watts with what I have...........but that extra 155 watts surely makes a difference in performance, but I don't want/need more heat in there either.
I did a rough calculation and figured I've used them about 16,000 hours in the 3 years I've had them. I would guess they would surely last at least 24,000 if not more anyway- I think thats the number I was quoted by Gavita customer service.