[Petseal]

I am in need of some help!
I have two Tactical Force M11 AirSoft machine guns. One works great, I plan on modifying this one to resemble the prop gun used in the Wesley Snipes' film "Blade".
The other will not fire properly. When cocked it fires then just leaks gas.
So I took them both apart and compared them to each other. What I found in the broken one was a whole section that has broken away and is missing. This is the cast metal part with the plastic inner valve(?) were the gas comes threw to push the BB down the barrel. It also has a spring loaded metal rod on top. Below are 4 pictures of it from various angles.
I tried to do a search for gun parts, manufacturers sites, diagrams or exploded views, or anything that popped into my head but with no luck. As I was looking for the best thread to put this post found several other threads which I looked over, still no luck. The problem is I have no idea what this part is called so doing a search is problematic at best.
So I am hoping someone here may know what this part(s) are called or better yet know where I can purchase them, or even better still have the parts I need!
Needless to say ANY help would be greatly appreciated!
Thanks in advance, Petseal