Looks to be a budget build like mine. VS cam, 90 springs, intake, headers, and the rest stock. Use a JY block. I also ordered a TEP trans. A few things I ended up spending additional on..... Valve spring retainers since stock retainers on the LS6 90 springs results in wrong installed height. Reuse stock keepers. I also rebuilt the supercharger snout, new idler and tensioner pulleys, new motor and trans mount, TTY head bolts, reusable rocker arm bolts, new stock timing chain and tensioner. These little things add up but help improve reliability and might as well replace it while you are in there.
I personally wouldn't rebuild a stock motor either. Poor return on investment. Run a junkyard lower block. I also wouldn't pay to port with such a mild cam unless you are doing it for free.