If the after market switches you bought are not working then it could be one or any number of things.
1) The electrical switch and ignition lock are not properly aligned
2) The electrical switch is not properly seated in the steering lock housing
3) Your ignition lock is binding and needs to be serviced
4) Your steering lock housing is damaged
5) Someone has bastardized the ignition assembly and the parts will never work together because they are not compatible (happens more often than you would think).
6) Some or several of the reasons above
I recently had a customer that sent me his 70-71 ignition switch to repair and get keys made. I fixed it and diagnosed the problem. He also needed a new electrical switch as his oem German 914 switch had been mangled by a previous owner. I located a NOS made in Taiwan switch for him and everything turned out fine. It was a repop VW 4 wire style just like the one above, just vintage NOS. I think you may have another problem not just the broken Bakelite portion. I work on Porsche locks. I can take a look at it for you and tell you definitively what is wrong, but I would need to have it in hand. You can see some of my work by following the link. Let me know if you would like to send it in.
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