While I understand you need some guidance--and preferably an on-site mentor--I'd really hate to see you replace an entire engine because you've maybe got one broken valve spring.
MAYBE the valve is seized in the guide; or bent. Maybe it's not as simple as a popped valvespring--which would be really easy to replace.
Point being, I'd like to see more diagnosis of what's actually wrong.
OTOH, GM sells the emissions-legal 383 engine package, you'd re-use little from your existing engine. Intake manifold/injection spider, and all the accessories--alternator, ps, A/C compressor, exhaust manifolds, etc. Everything you re-use needs to be inspected. Common for the exhaust manifolds to be cracked, for example.