Generally any strain producing the EcoRV restriction enzyme would also produce the methylase which is what you are looking for. Are you sure your plasmid does not also carry the methylase gene on it?

Thanks, Michael J. Benedik no methylase :-(

It has certainly been cloned and lots of studies done on it. My suggestion would be to see if someone like New England Biolab could share it (they have always provided strains and clones freely) or in this day and age it might be easiest to just have it synthesized into a plasmid backbone appropriate for your needs.

Michael J. Benedik thanks! haven't though about NEB!