My 1960 235 rebuild with .060 bore,crank turned .020, head and block trued, new cam, lifters,oil pump, bearings, valve job w/new valves, guides and seats, full flow oiling drilling, repair sleeve on crank rear seal surface, crank tapping for harmonic balancer bolt, full assembly (minus manifolds), dynamic (spin) balance of all rotating assembly components, will run me $2300. bucks. All replacement components are named brands...no brand X stuff!
However, I'm catching a little break because I haven't put a "RUSH" order on the engine. My builder has worked it in between commercial jobs and he likes simple old inline engines.
Just a suggestion...if you're going to do your own assembly, I'd borrow a beam balance scale and make sure your pistons and rods were close to factory specs. My engine was a compilation of mismatched parts that would have resulted in a real "shaker". BTW....$400. doesn't sound unreasonable for some quality prep work. Hope this helps.