KWA AKG hopup parts

[stryker20000]

So I picked up a second hand KWA AKG 74M. Needed a new bucking, yet I can’t find any in stock any where and I’m waiting for KWA to even get more made. I was notified that KWA possibly upgraded the hop up unit a few years ago, but can’t really find any info on it. I even contacted KWA with no help. Does any one know what parts, of any, where upgraded besides the bucking?  Even third party recommended buckings don’t work. Even tried a VSR for giggles.  Any help with understanding what I could do next would be greatly appreciated. Attached are photos of the current inner barrel