R22 Prices

I have an older 4 ton AC system, installed ~1997 that runs on R22 coolant. It has been poorly cooling the last week or so, and I figured it was poor airflow from a dirty filter. Replaced my air filter and called a tech from One Hour Heating and Air. He cleaned the evaporator and condenser coils but said I was about 5-6 pounds low on my R22 coolant and had a leak somewhere. Buddy wanted > $2000 for 5 lbs of coolant installed. Some quick googling suggested that is way too much money, it should really be ~$1000.

Does anyone have a recommendation for a company that will refill my coolant and fix the leak for a more competitive price?