Reddit mentions of RaceFace 104mm Single Chain Ring

C'mon man, everyone's doin' it...

Since you are deciding between 1x10 and 2x10 (indicating some apprehension of being limited to 10 gears), if you decide to go 1x10, best thing to do is to get One Up's cassette modification kit to widen your gearing range. In that case, you will just need:

• A new Shimano cassette, as normal.
  
• One Up's 42 tooth sprocket. (You can also get the 40-tooth if you think you don't need so wide a range.)
  
• A front chain ring (go with a narrow-wide design to help keep your chain in place). Here is One Ups's, which is a few bucks more, but gives you spacers so you can use the bolts from your old configuration. A little cheaper is raceface's chainring; not sure it comes with spacers though.
  
• Get a new chain. KMC 10 speed is fine.
  
• Tools: an allen key set, cassette lockring tool (with a wrench), chainwhip, and a chainbreaker tool.
  
  Setting it up is easy, pretty much take out 2 sprockets in the cassette, and put the One Up sprockets in the proper locations. And there are plenty of online guides re converting to 1x10 from the 3x drivetrain (also very straightforward).