HW99s / Plugging open sight holes

[Guloluseus]

You could go for black grub screws, either slotted or hex head as you prefer. Not sure on size but could check mine later if it helps and give a supplier link.

[luckymjr]

You could go for black grub screws, either slotted or hex head as you prefer. Not sure on size but could check mine later if it helps and give a supplier link.

Any more Info will be greatly appreciated, thanks