Looking to volunteer medically abroad


My nursing school is offering a medical mission trip just over the border in Mexico (we stay in southern TX). Despite being accepted, I have decided not to go because it is around $1,000 for everything and we're only there for 2.5 days and we spend more time doing mission work than medical work. I'm all for both, but if I'm there for 2.5 days only and spending $1,000 (airfare is $550 alone because we fly into a small airport) I'd like to spend more than a few hours in the free clinic! Anyway...

I'm on the hunt to spend my approximately $1,000 a little bit better! I REALLY want to volunteer medically abroad (mission trip or not). I found a few trips in Africa and South America (which would be amazing) but they are over $3,000. Unfortunately, when I moved a few years ago I never joined a church so that's not an option for money. Most of my friends are still in school like me and my family is helping me pay for school and they certainly don't have any extra cash laying around so financially, it's all on me. Does anyone know of a reputable place where I can spend 5-7 days volunteering in any underserved poverty stricken area for less than $1,500?? I'd like to someday do Doctors Without Borders or something similar long term and would LOVE to get started now.... I just don't have a ton of money to pay to work for free unfortunately.

Any help would be greatly apprecaited!

P.S. I graduate in December :)