I ordered a small bottle from Amazon for about $20 shipped. It's concentrated so you'll want a spray bottle and maybe a small syringe as well. You mix a small bit in with water and spray it onto surfaces. The 3.4oz bottle has lasted nearly a year so far.
I was curious because I did some research on it and there's a foreign place that ships it that is not the same as the original. They claim to be the same but they are not.
Mirage came out of brumation on April 26. He was doing great. On May 2 he started acting funny. We just redid his tank, and he keeps going into one of his hides. He just lays there. He shows no intrest in food. HELP!