Twin Famicom diode replacement part?

[chriswy27]

For my Twin Famicom I'm trying to source a replacement for the orange diodes in the picture. One tested bad with a multimeter. The only marking on them says 12C. It looks like they may be a 12V 0.5W DO-35 Zener Diode but I am completely new to this. Hoping someone in here can help with a comparable replacement part number

[krzy]

It might be BZX12 (12V zener diode), but I recommend desoldering it and taking a good lok around its glass body, maybe there is any more marking.
If it was part of supply voltage unit then zener diode would act as a reference voltage. However, I see there are 8 diodes, rather used as a some kind of protection (clamp diode) or maybe they are used to block current flow in one direction (kind of keyboard matrix scanning) and they are regular diodes.