Gary,
Is the MB 206 filling? If so do not bother to check the sac, it should be ok.
Don't send that 206 to MB, they don't have the parts and probably not even the skills for that sort of repair. It is rather easy and you can do it yourself.
I have some 206 and I can do a photo manual showing how to open it and change the sac. You will only need to buy a sac and some shellac. If you are in US David Nishimura can help you, if you are in Europe, Peter Twydle can help you herethere also.
Let me know if you need help
That would be exceptional if you could do a photo manual!
Gary