I'm also working on this Cosplay and I have some idea where you can get some of the gear, the vest hes wearing is a chest plate
This is a good example of what to look for your chest vest.
Once you look at the chest plate and pockets then that should fall in place for you.
Then its the jacket and pants it kinda gets tricky there cuz nothing will be a 100% match my best recommendations are as follows
same things with the pants they aren't regular tactical pants so your going to have to pick the one you think matches best
I went with the tru specs pants.
The reason i went with these pants is because if you look closely the bottom of his pants have pockets so I went that direction.
All the tactical gear on his legs is blackhawk products and the knee pads i just got the closes knee pads that I find could match.
In the end i would have to say this is the closes to a military costume that Capcom has done for Chris but again your gonna have to aim to what you feel matches the best because they don't give a break down of his gear like they did for Piers stuff.