You can't. The stock buckings on marzuen type 96's and its clones aren't AEG buckings, and aren't sold separately.
This has been discussed before, and your only option is to get a PDI chamber, AEG barrel, and a new AEG bucking...around $100 minimum. However, it won't be wasted as it'll significantly improve your weapon if you choose to do this.
This has been discussed before, and your only option is to get a PDI chamber, AEG barrel, and a new AEG bucking...around $100 minimum. However, it won't be wasted as it'll significantly improve your weapon if you choose to do this.