Slowtwitch.com has a very active classified forum. (Triathlete forum) Got shifters, a tribelt and cranks there.
EBay got CX frame, stem, seat post, pedals,,34t ring.
CL for an Ultegra wheel, bars and saddle.
Brakes from a member of a group on FB.
Derailleurs I bought new online, they are pretty cheap on EBay.
All but the frame and derailleurs were very budget priced.
Took many hours of searching over a couple of months.
Still looking for more Ultegra wheels and repair stand and a garmin.