Time for Oil Change - Recommendation

I'm a new owner of a 68' 440 Barracuda. I'm looking forward to putting fresh oil in the beast this weekend and was hoping that I could get a recommendation on the best oil. Should I go Synthetic? What weight?

The engine has about 10k miles on it.
Specs:
440ci balanced engine
Keith Black 10.1:1 pistons
Ported heads
SS Valves
1.7:1 Gold Crane roller rockers
Mopar Purple Shaft cam 284 degree, .484" lift
Mopar Performance Intake
750 Holley (3,000 miles since new)
Schumacher headers

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Thanks!