I thought an intelligent post from the other side would be......
Here are a few 340's for sale locally to me on CL, and they are 500 for a good short block.
Then I'd add A, B, C, and D with the remainder of my 2500 hundred and that would cover all gaskets, heads, cam, intake and carb.
I think this build would be a better performer than the 3k into the 318, still making the 340 the engine of choice for performance between the 2 engines even on a 3k budget.