building a fal can be done easily enuff if you make your own tools which is pretty straight forward for a person handy with simple tools around the house, so if you want a project I say go slow and measure measure measure before doing anything and be sure of what you are doing.
To me the $$$ comes out roughly the same when all is figured up and considered (time included!), maybe a c-note or 2 on the have it built side??
you'll be fine.
having said that it's just as easy to send off the barrel and recv'r to a competent 'smith and get it barreled and headspaced:
Mark Graham-Arizona Response Systems
Ken Kubin-Global Gunsmithing
Randy Kline-Sledgehammer Arms Works
Jim Gravitt-Pro Tech Engineering
are just a few but plenty others are out there that are just as good.