What's your budget?
...
Now double it.
I've had two places, who got the engine for $500 from a running old truck, quote me $3,500 out the door.
This isn't going to be a built up 350 to start. Here's the (mostly) complete part list minus the exhaust which will be 2.5 with straight through mufflers. Basically the total in parts below plus engine comes to $1,600; and they are charging the rest as labor (69 an hour x 26 hours).
Again, they aren't doing any rebuild on the engine right now hence the cost. If they were swapping heads and the cam for me, which I'll have done next year, that'd add another $2500 in parts/labor.
I wish I could find a shop that would swap the heads on the engine and cam for another $1,000 in labor but that's not going to happen so I'm getting a stock 5.7 swapped in for $3,500.
People quoting higher prices are typically adding to/rebuilding the new engine, because 27 hours for a carbureted swap is very fair for labor.
Edit: and to be clear, I'm happy with this price and the guy doing the swap is a Genius and has built amazing Montes. I'm really just worried he might get busy and decide he can't/won't do it. So I'm seeing what other people had done and for how much.