try Christian, he is our man in Europe for Beogram 4000 inserts :-)
https://leicht.io/articles/replacing-the-broken-pickup-mount-on-the-beogram-4000
Christian's replacement insert is printed on an HP Multi Jet Fusion (MJF) printer with PA12 Nylon with 40% glass beads.
He choose the MJF technology since it guarantees perfect layer adhesion and the PA12 nylon with glass beads since it improves product stiffness and structural integrity. Furthermore, it reduces warping and is good for functional parts that require high strength and dimensional accuracy.
I have just placed an oder for one of these inserts for my Beogram 4000, cannot wait to get the 4000 working again :-)