I found pictures of a new Siderail from Steyrarms Austria and designed it for my Airsoft-AUG as much identical as possible to the original, based on the low quality pictures. You need 2 short selftreating M4-screws and drill 2 holes in the right side of the receiver. If your AUG comes with the short siderail you must unmount it and drill the forward hole for the new siderail.
3D PRINTING SETTINGS
EXTRUDR GreenTecPro black, 225 Grad celsius, 0,2mm layer, 3 shells, 100% infill, supports
UPDATE 2024-08-05:
added a rugged version that should be stiffer.
The author marked this model as their own original creation.