I would check out Indiana Oxygen. Not sure what they charge for a tank but anywhere you go they are not cheap and refills are only 35 dollars. Most tanks the size for like a pepsi machine are around $75 may sound expensive but it will last you forever depending on how many tanks you run. Ive had one for about a year without having to refill. I believe mine is a 50lb canister with a TW of 25.4.