oil pressure spring plug

I cleaned up the passages in my oil pump and block. I need a new cap for the oil pressure spring, but I don't need to purchase a new high pressure spring kit. Does anybody know where to get just the plug. I have done searches here and find many mentions of the plug, but not where to get one by itself. Seems like it should be nothing more than a $1 hardware store item. Google yields threaded pipe fittings or push on pipe fittings but not a push in type needed.
Thanks if you can provide a source

UPDATE; Dorman 555-011 works perfectly. $0.58 at OReilly, Advance, etc.