Deepfire have a new version of their AT4:
<Deepfire AT4 – New Version>
UPGRADE: More easy to remove and replace the Cocking lever
Now you only use a screw driver to remove the broken pin if cocking lever accidentally breaks, and turn a new cocking lever clockwise to screw in the pin.
For the new order! We will provide one more pin to you!
DeepFire website: http://www.deepfire.com.hk
(Deepfire)