Prescribed Test in the US would come in a max.concentration of 200 mg/ml, therefore a dose of 400 mg would be 2 ml or 2 cc's., not very much volume wise.
I pay for my Rx; for 2 - 5ml vials of Delatestryl - $67.15 Cdn.
As far as how much you can gain, I really don't know what you would expect because of your situation, sorry. Maybe someone else can answer that for you.