how does this look to you guys?

$89 Stripped lower
$54.95 Lower parts kit
$79.95 Stock

$289.95 complete upper

total =  $513.85

This is still less than a vector arms uzi. Am I missing anything?

Lots of ammo.
good luck!

You are missing something. As stated on the listing page for 'barrelled uppers':

"Carrier assembly, and charging handle are NOT INCLUDED. "

how about:

the MEGA lower from carricozarmory (excellent guy and lower to deal w/ by the way) for $89
JTDistributions M-4/ CAR-15 kit for $450-$600 or so depending on what you want; i.e. chrome lined bbl, ergo grip, differnt handguards or stock

personally, i'd just go w/ a CHROME LINED bbl and chamber as my only add on on the CAR kit for a total of $499, and you get the charging handdle and bolt assembly