Help Save Stanley's Leg!

Stanley is my 7 1/2 year old pound puppy-pit, and is the love of my life!  He has had two surgeries in the last 5 months to remove mast cell tumors, and now requires 3.5 weeks of radiation treatment to save his leg.  Unfortunately I have maxed out the claims for cancer/tumor treatment through his pet insurance, and have to pay the $4000 on my own.