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That's the one I bought, though I believe it can be had cheaper if you look around (I paid 33$ for mine). That brand does sell versions for two or three monitors as well.
You should get 3 single monitor mounts. I went this way and couldn't be happier :) It allows me to manipulate each monitor any way I want, lining them up is easy, and there's not a lot of weight on any single mount. They also have cable management snaps built onto them.
Articulating Single Arm Computer Monitor Desk Mount for Monitors up to 27"
looks like the one i just bought.
These aren't ridiculously expensive.
One that has the vertical movement. It is more expensive
A slightly cheaper version