There are mods to equip PC/cNPC's with movie-Mandalorian style armour in K1 but not to change the Mandalorians in game to use this armour.
Someone experienced with modelling and introducing new appearances into the game could probably adapt one to the other I presume, so theoretically someone could mod it with already available material.
It's just that existing mods need to be tracked down and permissions gained, then somebody experienced and knowledgeable needs to do the work...
Alternatively someone experienced and knowledgeable could convert Movie Mandalorians 3.0 to a K1 installation, but I've no idea how to do that either. Plus it's not widely advertised information since porting existing models between games is against site rules (due to intellectual property issues between BioWare and Obsidian I assume), so the few people who might know how to do this probably aren't going to start posting tutorials.
It's a matter of finding someone interested in doing it, who is willing to hunt down original mod author permissions for a public release of a modded mod.