Kmz Horizont apeture ring insert replacement

[8bitmime]

Hello everyone,

Long time reader first time poster.

I recently bought a kmz horizont for a (relative) steal but on my first outing with it the apeture ring insert (the black metal ring that has the apetures printed on it) fell off and is gone. I have made a stand in from an aluminum can and some paint markers but I was wondering if anyone had an idea on where I could find a better replacmenet? I was thinking about 3d printing one as well, I could post pics / .stl files here later if I go that way for any other unfortunate horizont owners.

Thanks!