Actalis, based in Italy offers a free tier, with ACME https://www.actalis.com/subscription

ZeroSSL from Austria also has a limited free tier. https://zerossl.com/pricing/

I mean really, if you use lets encrypt for anything that runs in a production environment, the responsible thing to do is build a fallback to switch to another provider in case LE has a bad day (or hits a brick wall and needs to say, enforce export restrictions).

Worth noting that Actalis requires you to register an account with them in order to acquire the necessary authorization token for their ACME API. This poses a privacy/anonymity issue for some users. Last I checked, Actalis' free tier didn't support SAN either.

Add.: I created an account just now to see "what's what" and also found the notice, "Activate your free 90 days certificates. At the end of the free year, the services associated with the certificates will expire." which sort of sounds like it's just a 1-year free trial.