How to allow all three foreign ironclads in FOTS?

[Dahak]

I am trying to make all three foreign ironclads recruitable from the drydocks (for everyone) with no build limits, but I just can't get it to let me recruit all three. Removing the build limit and adding the ships to the drydocks was easy of course, but it looks like the selection you make for foreign trade deal prevents you from building the other two ironclads. Is there any way to fix this without having to dupe all three and make drydock variants?

I couldn't find anything relating to that event in any of the tables that usually restrict units. In game the drydock lets you build the one from the event pick, and shows the other two ironclads but has them grayed out as unbuildable.

[Jon_the_XII]

I would just make new units and clone the stats and uniforms from the Ironclads. Note that Ironclad and other naval units use naval_uniforms_tables and unit_stats_naval_tables instead of uniform_tables and units_stats_land_tables.