Reddit mentions of Avid FR-5 Bicycle Brake Lever (Silver/Black, Right or Left)

If you know the shop guys, they might do it for free if you bring 'em a six pack. If you buy the brake from a shop, they might install it for you.

Honestly, though, installing brakes is pretty simple - you remove the bolt and washer, slide the pin in through the hole in the fork, and then put the washer and bolt back on. Tighten it down. The rest of it's just getting the cable tension and pad placement right, which you'll need to deal with on your own some day anyway.

The lever, on the other hand, depends on what sort you're going with. There are basically three options (I'm linking Amazon, but that's just because it was easy for me to search; you may find better deals than what I'm linking to, I just want to be clear about the sorts of levers I'm talking about - and furthermore, the ones I link might not even match the bar diameter for the bike in question):

• Bar-end levers pretty much only work on bullhorns. I believe that some will work fine with chop'n'flop bars and some will not.
  
  
• Road levers will look a bit goofy mounted on bullhorns, but will totally work.
  
  
• Mountain-style levers - be careful that you're picking up some that will fit road bars, and be careful that they have the right amount of "pull" (this will be dependent on the set of brakes that you have).
  
  If the bike comes with a brake, I'd try mounting that on the front first; if it works, you've saved yourself some money, and if it doesn't, you may gain some knowledge about what in particular you need (possibly, for example, you can get by with just getting a different center pin).