I don't like the EFF, but I guess I will have to use Let's Encrypt if there's no other option.
The suggested client, CertBot, is an EFF project, but there's a wide variety of alternatives - https://letsencrypt.org/docs/client-options/
I'm not the kind of person who believes in boycotting (especially in this case, where I'd be all alone it seems :-) but if I could avoid them, I would. If not, no biggie.