Since you are 81 years old, your mother had she been alive, may be at the age of over 100 years now, well she is reported to have passed away 25 years ago. However do you have property records namely sale deed on your maternal grandmother's name?
Are you aware of the mode of sale by your uncles, i.e.,whether they sold it on the basis of shares allotted to them, if so do you have a copy of the sale deed.
There are lot of questions to be answered in this regard including the maintainability under the original Hindu succession act, because daughters were not entitled to any share in the parents property prior to the amendment made in year 1956.
You should consult a knowledgeable and skilled advocate in the local for further opinion based on the relevant documents and facts of the case.