Following on from my Diana 35 thread.
It came to me missing the rear sight but wearing an early aperture sight.
It functions well enough but is missing the eye cup.
Bicycle tyre tubes can be made into functional items but I would rather not embark on that solution just yet
It requires something in the order of 40mm diameter.
Any suggestions where I might find a close replica of the original item?

https://c1.staticflickr.com/5/4222/3...ce2770c8_c.jpg

https://c1.staticflickr.com/5/4250/3...f0c5951c_c.jpg

https://c1.staticflickr.com/5/4200/3...05e606ed_c.jpg

https://c1.staticflickr.com/5/4248/3...037ba50d_b.jpg