I have an old "Favorit" racing bike from Czechoslovakia and I'm missing some bolts on the chainring. I went trough some bike shops and couldn't find a replacing one. The bolts diameter is slightly smaller on mine which make the new unable to fit.

I would like to keep the "style" of my bike as intact as possible. I can see two options here:

• Find a website with such old chainring bolts (if anyone got any tips here, I've been pretty unlucky so far)
• Make the hole in the chainring slightly bigger (by using a file?).

What would you recommend? Would option 2) be even possible?

Thanks in advance!