Telstar AR 1985 - No enging cranking

[Flokos]

Dear all,
As I continue the maintenance of my beloved car, after 2 days of colder nights, I could not start the engine properly this morning. First attempt of turning the ignition key indicated a lethargic battery as cranking was attempted. The second try just caused a super-quick rattling noise inside the distributor. I've changed the IC box at the back of the distributor and replaced it with a new one - the same result. I've checked the inside of the distributor ''cylinder'' and inspected the 4 contact points (for the ignition leads) and the central rotating arm - looked fine). Ignition leads and spark plugs are OK. I have not yet changed a NARVA relay switch that has leads towards the starter motor. But, as the first attempt showed an almost dead battery, I suspect it as the cause, even though I've recharged it a week ago, and the car was doing fine....
Your advice would be appreciated. Thanks, Flokos