If I were pulling down a 69 318, a timing chain would be among the required list of things to do to it. Rings, bearings, timing set, gasket set, oil pump, water pump, fuel pump, umbrella seals on the valve stems(come with the gasket set), Clean out the heated air passage in the intake, hone, assemble, and install. Then fresh plugs, plug wires, cap, rotor, oil, and oil, fuel, and air filters.

Anything less always resulted in them needing to being done in short order anyway. Its easier to do it all at once. Gene