Here is what I would build.....I used your list my comments beside it
1.new comp preped block
2.5140 forged steel crank (4340 Forged crank is more common and stronger)
3.4340 forged h-beam rods
4.forged probe pistions
5.molly rings and clevite bearings
(331 or 347 stroker kit, Scat H-beams 4340, Scat 4340 crank, rings, bearings, Probe SRS series pistons, all ARP hardware $1500)
6.afp fasteners ($100 for ARP head studs)
7.302 main support ( $300 DSS support comes with ARP main studs)
8.h.v. oil pump ($60 including hardened shaft)
9.balancer and flywheel ($238 Romac, $300 for a SPEC flywheel)
10.billet timing set ($100 for a Crane or Rollmaster)
11.fel-pro gasket set (For a shortblock you need about $80-100 in gaskets)
12.tfs alum heads or pro-topline ($1285 AFR 165's or 185's)
13.motorsport hyd roller lifters ($109 fms)
14.hyd roller assembly (Custom Cam FTI $325)
15.manley push rods ($100 for TFS chrome-moly 1 piece)
16.scorpion roller rockers ($200 1.6 ratio)
17.engine is balanced , blueprinted,comp assembled (Runs around $600 total)
Total.... $5317 so you can see $4200 is fairly cheap for what you listed. The biggest difference in my list is a 4340 crank +200 or more, FTI custom cam +100-150 over other, AFR heads +200, balancer and flywheel ( I picked 2 of the better names out there)
Add another $269 on for a good 7qt oil pan, pickup and dipstick, you'll need it to clear the high volume pump and girdle.
If the internals or any components are CAT stay away they are junk, usually if it was a good brand name they list who it is.....