I see your note about not wishing to subscribe to our service. I will send a not to Customer Service to that effect.
However, since I am already here, I'll just go ahead and answer your question, which is a good one.
First of all, I should tell you that the best way to get a complete and reliable answer is to make an appointment with your mother's local Social Security Office for you and your mother to go in to the office in person. If you don't have an appointment, then the wait can be somewhat lengthy and cumbersome and not that comfortable in most of the local offices. If you mother is not able to accompany you, you will need her Power of Attorney in order to obtain her & your Dad's personal social security records.
As your Dad's widow, she would have been eligible to receive Widow's benefits at age 60, unless she had dependent children under age 18 at the time, which seems could have been the case given your mother's age.
In any event, that is the only way to obtain the information, unless you and your mother want to try calling, but that can be an arduous and time consuming process and not always productive in terms of receiving accurate information.
To reach your local Social Security Office for an appointment, go to:
Finally, there is an online option, but with your mother's situation it may be difficult to obtain the specific information that you seek, as I mentioned above. You or your mother would need to set up a personal account for her at ssa.gov. You can go here to see the extent of services provided online:
Hope this helps in some small way & I'll make sure Customer Service know that you do not wish to subscribe to our services. If I have been helpful today, I'd appreciate it if you would provide a rating in order that I may receive credit for assisting you this morning.