I am not familiar with services at the U of Arkansas. If finances are limited you probably don't want to travel huge distances. You could go to www.aao.org and look for a oculoplastic surgeon.
In St. Louis either Washington U or St. Louis U school of medicine Department of ophthalmology are very good.
JCH MD
My sister lives in Bella Vista, AR, and has family in Kansas City. What hospital center would you recommend in the Midwest?
Your sister obviously made a serious, maybe life-threatening error by not having the tumor removed when it was smaller. She needs to be seen at a medical center, the tumor will probably have to be debulked. Social services at the medical center can help you with your other questions. I would suggest the U of Washington Medical center.
JCH MD