^^ Yeah, if you're running a freewheel, you need brakes. Otherwise, you'll need a cog and a lockring.

One big thing you're overlooking from a compatibility standpoint is the seatpost (and possibly seatpost clamp) diameter. I don't know what this frame is, but poke around. For some re:tarded reason, seatposts are sized a 100 micron level.

E: how about a headset?