Need help on 49 Chevy straight 6

[The Big Green]

The engine is original and I would love a 350 in it but can't part with the matching number engine and tranny. I want to keep it bone stock with the original engine. The engine wasn't locked up but because of the 4 vent holes in the stock valve cover things got in over the past 30 years, there are spider webbs under the valve cover. I want to rebuild this, it sit 30 years ago because of a bad starter, and now needs rebuilt,with new gas tank(rusted thru),starter, carb, and the distributers cap is off. I can't find a place to buy anything for this engine, internal of ex. I don't see a reason to change up a truck that may have been gutless back in the day but indeed built alot better...stronger. Wait and see an 08 in 60 years...lol. I need a good place to buy these parts, not sure about the local autozone...lol. I bet this engine would start if the wiring wasn't so crispy. As for the wiring harness, I found all of it for like $350 maybe, if I'm right and it included extra wiring for turn signals, it was the original wiring so everthing would be put back like it was new.