Oh, come on- we start throwing out hypothetical baloney builds for the guy (who even said he would prefer to build this motor), and then you have to chime in and try to be the voice of reason. You're no fun.
:lol:
Granted, 8 sleeves at a c-note per hole ain't cheap, but there's no guarantee a different engine won't need work, too. What it does get you is into the realm of more readily accessible parts (I.E. pistons).
OP, all joking aside, even though you have access to a $3200 360 crate motor (I don't recall seeing it be a "Blueprint") I do think your best bet is to just find a decent 5.2 Magnum (318) to drop in. Most of these things have worn really well, and the most they need is a dingleball hone and a set of rings. Most times they don't even need that. All you'll really need to buy is 4 things: an LA360 oil pan, any of the "chinagap" 4bbl. intakes, and the crank hub bushing (if it's an automatic, a roller pilot bearing if it's a manual), and the cam snout adapter from Hughes. EVERYTHING else is easily adaptable from the 273. Your 4bbl. carb, linkage, TC cover/wp/fp (even the balancer if necessary), distributor and all accessory drives and pulleys. Bone stock cam with a 5.2 will still probably put you in just between 250-275 hp. on pump regular.
Last time I got a Magnum at the Pick 'n Pull, it was a 5.9 version for $200 on half-price day (yes, this was pre-Covid, but still...) The above parts shouldn't set you back more than $300, plus gaskets.