I'm not sure where they ended up in developing their own parts. Initially they were based on quite a few of the No4 small parts, but they moved away from them. Your only hope would be if a gunsmith can recognise the shape of what was needed and make one from scratch. I have to this day, never heard of anyone successfully finding spare parts or any other support for these rifles.
Maybe someone here with one can help you out as to what you might be looking for, but everyone needs to know, if you break it, you will possibly never fix it.
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