I have the ones ordered for me by the lymphedema clinic and you are right-they are expensive. The way they decided on the right size for me is they measured my arm from my wrist up to my armpit about every inch and one half and then compared my numbers to a chart to get the right size. If you could measure your arm and have some guideline on the athletic compression sleeve to go by it might be okay. I think you need to have the right amount of compression to help the fluid move, ergo all the measuring! Good luck!
My LE PT thought that my UnderArmor comptession top was great formy truncal and axilary LE.
You also meet the correct pressure for the sleeves. The ones I have seen range from 10-20u, 20-30u and 30+u
My insurance covers the cost
Lymphadema sleeves are measured to fit just you