I think you are looking for the Fujimi, Tamiya and Hasegawa 1/700 scale waterline series ships mostly, eg you've found the Shinano parts, there are lots of these and gun nests from other IJN and USN carriers too, but the parts you've asked about definitely look USN don't they?
As Jedi Dade says, there are a helluva lot of battleship gun barrels, usually triple or quadruple but some double too. Not just in the edge trenches, they're all over the tower, engine bay and superstructure too. There are big chunks of battleship superstructures all along the edge trenches also. I think you're looking at British and German ships for some of these, and probably therefore at Airfix 1/600 kits as well as the Japanese ones.
Cripes, really if you are seriously looking at doing an 8.5' SS replica I'd guess you'd be looking for almost *every* 1/600 and 1/700 scale warship kit that was available at the time. In multiples, so a good supply of silicone and resin would be a must! Scary. I'd love to do a decent ISD some day, but I think I'll settle for a reasonable Devastator replica instead.
Many people aren't aware the 8.5' model is asymmetrically detailed. The port side is the 'hero' side for closeups and much more heavily detailed. You could save money and time by copying the starboard side only? Still a job I'd be scared of myself.
Cheers!
Martyn
