You can purchase esttriol cream over the counter. You can try checking at your local pharmacy. If your pharmacist can't get it, then look on Amazon or other similar sites for a product called EstrioCell which is estrio cream.
Estriol cream is available over-the-counter. While it is not a prescription drug, it does have a number of applications and dosing, so a physician should be consulted in order to deliver maxiumum benefit to the patient,