Elgin Industries small block Chevy head bolt set part # EHC-99S Plenty of similar sets on Ebay for under $30.00.

https://www.ebay.com/itm/New-Complete-Cylinder-Head-Bolt-Set-Chevy-sb-400-350-327-307-305-302-283-267-262/221346976012?epid=222845399&hash=item33894ed10c:g:On8AAOSw7a9cvHh9

Torque to 65-70- ft./lbs. in the proper sequence from any factory service manual and don't bother with a retorque. They will last through several engine rebuilds with no problems. Your first, and biggest mistake was discarding perfectly serviceable original equipment bolts!
Jerry

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