New Bleed Nipple Thread Question

[Atari Boy 11]

I am going to be taking a rear calliper to a machine shop next week to drill out the broken bleed nipple.

Assuming that they can’t save the thread, what should I ask them to replace it with? Am I right in thinking that the original is 7mm? Would 8mm be okay?

 

I have done a search and could not find the exact answer.

 

thanks

 

Jonny