What is the reason for the 454. I would love to have a 454 big block in my vette but everytime i crunch the numbers a small block is always cheaper.
A 383 will pump out a nasty 400 hp and 100 pounds lighter and half the price. As mich as i like the big rats they are too much money unless your going with a new dart block for racing its not worth The cash for a mild build.
Also if your going to crawl over every junk yard ina hundred mile radius of your house build an LS motor. Lots of good options. The 6.0 truck/escalade motor is a nice choice.
Careful lots of different 454 out there. Some are newer roller style some old and some much older. And not all parts work with all engines. You will need to get your block tear it down and find out what you got before thinking about pistons. Wiki has a pretty good general break down. I think they have 7 generations of engines. Not all are really performance quaility.
But the cores are out there. They came and may still be option in 1 ton and over trucks. Lots of short school buses have 454. Just make sure you know what you want before you go looking. Junk yards will sell you the crappy engines first. A good early 70's core will be at a preimium price but a later roller truck motor is probably better.