There is no set fee of course. Every shop determines their own rates based on skills/experience, materials costs, costs of business, etc.
Whatever your time and experience are worth to you.
Are you a professional?
In what field? Photographer, framer, or other?
My hourly shop rate is $75 to $90 depending on the task and how much "extra" effort will be involved.
If the task is easy for you. (you have experience and materials to do it quickly and well) you might charge your "regular" hourly rate.
If something requires excess time, it's a skill you are not proficient at, need to get help with, need to gather supplies you don't normally have, etc. Then it is "more" work for you and you might need to charge enough to cover these "extra" costs of the time you spend to perform the task.
Most framers have a minimum service/labour charge that could be a full hourly rate, or a portion of hourly rate.
Ie: minimum labour fee of 1/2 hourly rate.
So, two questions:
1-What is your time worth to you?
2-Do you have the skills /experience to re-seal this frame to the same quality as before you disassemble it?