Condor bottle, where to get one?

Is there a source for bottles, either air or CO2 that is compatible and priced less?
The prices for these bottles is crazy!!!
Over $100 and close to $200 when Wal Mart sells CO2 bottles for about $30.

There has to be a way to convert the cheaper bottles to work.
I would like to get 5 -6 bottles, but not a AF pricing….

Any help would be great!!