Just wondering: is there a way to have a specific faction (not culture) based Ram?

In my remodded LOTR-TW mod I would love to give Mordor a huge Grond Ram, but given Mordor are romans_julii and there are other orchish factions (Isengard as brutii and misty orcs as scipii) giving romans the Grond will make it available for all three of them.

Which, reconsidering, may not be a bad idea ;)