Come to a PD match in Pueblo. Look around, ask questions, and most importantly get behind some different stocks. Stock selection is critical to shooting well, and they're stupid expensive so you want to get that right.

Cartridge selection is a big deal. Do that up front then go buy your donor action (long or short). There are lots of good barrel makers out there, and it doesn't matter a whole bunch which you choose.

You are going to need an action, barrel, stock, maybe a trigger, scope base, and glass. Add gunsmithing to the cost.