My ears say metal to metal interference, but I could be wrong.
I suggest the stethoscope and pinpoint the noise.
Getting it on the timing cover with the engine running can be tricky (and even a tad dangerous) but if it's the chain/gear set or the chain hitting the timing cover, you will find out fast.
The Goodwrench 350 that came in a truck I bought had a constant tick-tick-tick sound which ended up being excessive play in the fuel pump pushrod, due to the cam lobe that runs it being soft.
If you do decide it's timing chain and gears time, do yourself a favor and get the Cloyes double roller.
Stock link type chains are good for MAYBE 100K miles at the best before the engine loses a herd of performance due to late valve and ignition timing from the stretched chain and worn gears.
I put over 100K HARD miles on the 383 stroker I built 20 years ago, used a Cloyes set when I built it.
When I removed the timing cover to do an inspection, there was not enough wear or slack to even think about putting a new set on .....
WELL worth the few extra dollars !!!
And don't forget, if you install the gears with the dots close together, the engine is timed to fire on #6 cylinder.
Rotate another turn to have both dots at 12 noon for #1 firing.