Yeah, maybe, but mine is the older 4-pipe version.I think the 6 heatpipe models would do the job fine. That's what I had on my 8800GTX after all and it had no problem there whatsoever.
Maybe they're too small a company to keep much of an inventory, or have a manufacturer dedicate production lines to extended production runs...It's as if Thermalright builds one batch of every product they design and then they discontinue it.