Don't know how it works over there, but over here in Australia, last year my dad and myself had our motors rebuilt. Dads was an SBC350, mine was a 389. Our rebuilds were pretty much identical work wise except I had already had my pistons/bores done, bearings, cam and 1.5 gasket kits (had 1/2 a set left over from an old 455 build + beyond)
Dad's motor needed EVERYTHING, rebore, rings, bearings, springs, gasket kit, vales.. the lot..
Dad spent $2000 to get his finished, home, running. Remember its a stock motor +0.035 with a mild cam, nothing else.
I spent $2000 to get just the short block done! Where I did stuff up was trying to find rings for a 389 +0.040 in this country!, I should have had the bores machined the extra few thou and gone a std 400 bore and bought new pistons & rings. Dare say it would have worked out the same price!. Anyhow after I had the heads cleaned up, new springs, new valves, each seat has been replaced with a hardened insert as they have been pounded to nothing (1966 heads), my bill came to $1200 for the heads. $3200 all up for my engine before I spent any extras on valve covers etc.. This is for a stock 389 +0.040 with a similar grind cam to a RA3.
Honestly the 389 smokes his into the ground, but when the topic is dollar for dollar rebuilds in my opinion a chev is cheaper due to the scale of parts out there for the Brand-X market. Standard performance wise, ofcourse the characteristics of the Pontiac motor will eat chevs for breakfast (remember I said standard). But to do the things I would like to do, fuel injection & turbocharging, it leaves me thinking as I can do it with a chev for half the price as everything is just there for it! Especially a crate all alloy LS1 or something along those lines....
Its an interesting topic, but yeah thats my 0.02c on it