You have authorised Bose service centres in all major cities.. try them.
If you ready to pay your bucks for those old dogs (as you said) then here i am posting a link follow it, may help you out Speaker Repairing in Mumbai - Grotal.com
Else, as my friend said above Bose authorized service center is there in many areas of your city; but I guess their service will be expensive.
You're joking right! Anyway ... in case you didn't know they are pretty clueless.
Nikhil I sugest mailing rather that expecting the showroom or any service center person to call back