Replacing gaskets and cleaning up my SBC 400. Looks like my timing chain retainer is hitting the timing chain cover. I measured and it looks like it should have some clearance, and with a few thousand miles on the engine id imagine there would be more wear if it was constantly rubbing. Does the retainer move in and out at high RPM? Also, do I need a different timing chain cover?

If I just need a new cover, what do ya'll recommend?