Reliable source for quality 5.3 parts???

[Jl8806]

First post here but I've did a lot of browsing lately, so much that i cant remember everything... but i will hopefully be posting a lot in the future. I'm about to swap a 5.3 in my '97 K1500 and after this is done i want to find a 67-72 to build. For the '97 I'm looking to go for a stock look with stock parts, i want it to look like it came in the truck like that from the factory. The problem is I'm having a hard time finding parts and knowing where to find a reliable vendor to buy from and one that also sells good parts. I'm going to price stuff at the dealer but I'm sure they will be way to high on everything. I've messed with diesels for years and there are so many good companies that are pretty much one stop shops for everything you could possibly need, I've not had much luck finding a place like that for the ls... I'm going to go completely thru the engine before it goes in so I'm going to be needing a little bit of everything... Thanks for any help!