So, yes they just made a recent release of the Leo, it came out back in 2018 (There is also a Leo kit based on the Build series as well.)
The gun was hand painted, and was not the original gun, it came from a weapon expansion pack I got at a build day my local Gunpla group had (and I agree it looks a bit thick). I have the original gun primed, I just need to finish painting it.
For the paints I used Army Painter (Goblin Green for the body) for all of it expect the feet which was some Model Air paint from a German WWII air paint set.