With the recent events surrounding GTA leaks, I decided to re-create the iconic mission marker. Just head on over here and download the files for free; you can use them for whatever you wish!
The included files are the material, material instance and the actual mesh. To install drag and drop the MissionMarker folder into your project content folder. All I ask is that you rate the product after you've downloaded it, and that you head on over to my website and have a look around! I have created some really cool shaders and material functions that I would love some input on!
Also, the files will only be up for a few weeks, so get them whilst you can!