Go for the end users.
Lot of Bible folk in the US I believe? You should be spoilt for choice looking for a group willing to have that domain,
especially at this moment in time. (Google 2012, and Mayan Calendar, Precession Of The Equinoxes, and you'll see what I mean!)
To be fair, virtually ALL cultures around the globe have prophecies for this, but the 3 Abrahamic religions are expecting the AntiChrist dude as an added bonus. You betcha one of these groups will have the zeal to slap up a website with various 'testaments' warning us to get our acts together. Heh they are already doing it. But then so are the New Agers etc.
Yeah, I think you could sell it to an end user no prob, but probably only for a few hundred unless you can get one of the rich evangelists interested. Get emailing Pat Robertson and co!
There are other uses for the word testament of course, but I think the religious angle is your best shot. Or politics. The creeping fascism etc.
If other extensions of the term are listed in the $x,xxx then there's your starting point. Go for it!
Good luck!