Check out Sealant skeleton gun with cartridge 3D model purchase 3D model on CGTrader for $29. High-quality mesh by HQ3DMOD: 102722 polys, 103714 vertices. PBR, Textured, UV Mapped.
OBJ (OBJ, filesize: 3.88 MB), TEXTURES (Textures, filesize: 35.5 MB), MDL (MDL Material, filesize: 35.5 MB), MAX (Autodesk 3ds Max, filesize: 5.49 MB), FBX (Autodesk FBX, filesize: 26.2 MB)