If you want to use it in your next game, you can buy it here:
https://www.cgtrader.com/3d-models/military/gun/missile-turret-game-ready-pbr-textures
Here's my latest turret. I used 3DS Max for the modeling and baked it out and textured in Substance Painter. I rendered the images out in Marmoset. It's using 1-4k texture.