Goblin Riders

Does anyone know a quick way of replacing the goblin rider with the rider on foot? With the little I know of Blender and some .mdl editing with notepad, I can eventually replace the models by manually adjusting and copy pasting things, but I’m wondering if there’s a better, more elegant way of doing it instead of manually brute forcing it. I’d like to do the same with a few more goblin models, so you can tell why I’m looking for a better solution.