Especially because you live in NJ, you would be well advised to only consider purchasing a block with a PRE-1974 serial number. Since NJ requires your engine to have ALL emission devices present and operational for the year of your engine, pre-1974 is the way to go. I'm certain you don't want to have to fiddle with EGR valves and air pumps, etc. I personally chose a 1969 351W engine from a salvage yard and completely rebuilt it. You might try the Engine Factory in Lebanon, NJ (
http://www.enginefactory.com/). They have a good reputation for quality. Another good source is Jasper Engines. Either of these suppliers should be able to supply you with a pre-1974 serial number long block. You'll be glad you did in NJ.
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