Acrylic paints from a little-known manufacturer are used here. Most likely - this is just a repackaging of paint from one of the famous brands. The names are strange enough, but with explanations that might help us.
1. "Dark green 3B". "The main color of military equipment of the USSR before 1941"
2. "RAL 8017". Chocolate brown for German military equipment.
3. "Gymnasterka". "Equipment, ammunition". Here I find it difficult to say specifically what the manufacturer meant))) I think it meant the color of the Russian WWII uniform.
The last two colors were used to superimpose light and shadow, their names are not important.
I think it's not a big problem to pick an approximate color from the photo of the uniform. All the same, the human eye perceives colors differently depending on lighting and distance. It is important to convey not the nuances of shades, but the overall impression.
The most important thing here is the very simple technology of working with a good end result.