Ballpark :$3000-4000. for all you mentioned. Transmission is also another big expenditure if it's a hydramatic.  Thats why a lot of people say 'well for that kind of money I'll just buy a crate 350 because its  cheaper and more reliable'  Yep but it won't be a total Hudson. There's no right or wrong it's just how far do you want to go and what is it you're looking for.

Agree with Lance, if you are having a shop assemble the motor, plus machine work and parts, it will be over 4,000.
I have cars that have stock with mod drive trains and one with the 350 combo. I actually enjoy the stock with mods more than the 350 combo. If I were doing one right now and going with non stock. Id like to build one with something different then the 350 route.
But if your mainly looking at cost, nothing cheaper than the 350 combo.

You need to figure on 5-7 thousand for a top quality rebuilt engine that is ready to have the accessories hung on it and installed. This is what I tell anyone who has me build a 308 for them. If you are going with the 7x type mods and a bigger cam its going to be closer to the higher number. Most people are only going to have their engine built one time, and that is the time to do it all. after I build one, I run it on a test stand, with a full radiator, and check it for leaks, and go through three or four heat cycles, retorqueing the head after each one. Then when the customer picks up the engine, we start it up and run it so he can see that there are no leaks, and it runs as it should. Good work isn't cheap, and cheap work isn't good.

Good, fast, and cheap. Pick two.

Pick two?

Oh, I got it now —2 out of 3 ! LoL

Yes. Practically every “speed shop” back in the day had this sign behind the counter. It means you can only have two of those three things.  
Fast and cheap:  not good.
Good and cheap:  not fast. 
Good and fast:  not cheap.  

Written on the backside of those signs was the sentence, “Fully Satisfied customers far and few in between!” 

Well I think the responses to the original question are landing in a range of $4k to $8k which seems realistic to me. 

I’ll add a new 350 GM crate engine long block goes for $4k —$6k.  So I think one can safely say these costs are very similar.

In my opinion the 350 wins the performance category while the 308 retains originality and sustains the longer term value. 

I agree with Robert's analysis.  As soon as I get the head off my 308 I'll know which way I'll be going.  But my thought for a V-8 was to locate an AMC 327 and build the car that AMC should have built instead of the "Hashes"  that is to say an improved Stepdown chassis with the AMC 327 and a ball joint  front end .

Dean Prodromos

AMC 327 gets my vote. Different and well built motor.

I will be beginning a rebuild of a 308 twin h in January so will keep you all informed as to cost. Freight of rebuild items will be a killer as i am based in Australia.

Cheers

Steven

Robert, don't forget to add all the modification cost onto changing the power plant and trans to something other than Hudson. Rear end, wiring harness, usually dual exhaust vs. single, engine mounts,etc,..   Most anyone on here knows you can make 1000+ with a SBC, but with minor mods, port and polish, new cyl.head., a header, the 308 will out perform the stock 350, and/or slightly modified 350. Torque VS. rpm/hp  Don't forget the wow factor when you open the hood, still has a FLATHEAD under the hood!   Twin-H-Power adds to that factor too!.

Doug ---You are right. The 308's "wow" factor is definitely worth a premium! You almost always see this reaction from folks who have never seen this engine up close and personal. My favorite reaction, which I've witnessed several times, goes along the lines of, "Man!, that thing looks like a big-A tractor engine!!" Which it does,,,lol