Ford industrial 4 cylinder engines are also used in ford 8n tractors. Search for points for that and they are readily available or convert to electronic ignition using using the ford 8n tractor search. Good Luck.
I just went through our 4500 and revamped the ignition system to a pertronix system. Haven't had any issues since. Here's a picture of what our distributor looked like, and the electronic ignition that fit. Hope this helps