Columbia 201 soundbox

[ColJoe]

The diaphragm in the soundbox of my Columbia 201 portable needs to be replaced due to many cracks radiating out from the centre. After dismantling the soundbox, I am assuming that it is not the proper one for the machine, as it does not fit into the notch on the end of the arm but is held in place with a grub screw.

Can anyone tell me what soundbox should be fitted? As I am not too bothered about originality, this is a machine intended for use, can just the diaphragm be replaced? Are there other non original soundboxes that could fit it instead?

Thanks.

[MicaMonster]

If you can post a picture of the reproducer you have, that would help.