$5000.00 doesn't sound that far fetched. I built a 502 last year (actually my machine shop did) for $6000.00. That included block, .025 longer Eagle rods, 572 hyd. roller cam/lifters, pistons, 1 of my heads was trashed so I needed another casting too. The block alone was $1400.00 (used) so using a 454 will keep your cost lower. I didn't dyno it but I would imagine around 450 reliable hp. The only thing I was able to salvage from the old 454 was one head, the crank and some valve gear.