The Unity.45 Samurai Edition is a reskin of the base model Unity. It has no stickers and no, adding the stickers isn't possible (yet) I tried.

This mod will make the game a lot more fun and will give you a lot of new experiences.

You can find this variant of the Unity in CET with the command

Game.AddToInventory("Items.Preset_Unity_Neon", 1)

You can find the icons in this mod in the following files:

"ml_w_handgun__constitutional_liberty__base1_01_neon2_unity.misetup", "yaiba_stickers.xbm", "item_icons3.xbm"

The icons are an option included by default, you likely won't have any issues, but if it causes a conflict with another mod, you can delete Unity_Samurai_Icon.