Contact the closest university teaching hospital - that will be your best option to receive billing flexibility and perhaps charitable write-off.
As an international student, if you are affiliated with a university, you have the option to purchase student insurance. I would suggest that you do this for the future - it's too late to help you with this immediate surgery - but can save you significantly for future need.
It's expensive! That is all you need to know. You will need insurance.
I can't give you an estimate. It will be expensive as you will have surgical fees, hospital or facility fees, anesthesiologist, medications, etc.
Your bet bet would be to contact the eye centers you are considering and discuss with their billing services.
JCH MD