Nambu type 14 replacement parts

[justsomeguy]

Hello all,
I recently acquired a Nambu. It looked functional but after my post purchase breakdown, I discovered it was missing the locking block.
I can find all sorts of replacement parts but have yet to see a locking block for sale or anyone who makes replacement locking blocks.

Any ideas where I might be able to get one? I have a really cool looking paperweight at the moment.

Thanks!