Random Model Color/Texture

Basically, i want to give one item model several textures or maybe, randomize its color, like the "grass color" from minecraft and etc.
My idea is to make a syringe, and the color would change randomly. Example, if i use the syringe on a player, the blood would be a red, but in another player or another mob it would be a different tone of red. How would i do that? or maybe add several textures to 1 model and change it when i need to