I'm not sure where you're located but you could also try the local health dept in your area. In vegas we have one and testing there is done free, for I think all STD's. Just a thought.
And although you probably already know this, I do want to warn you NOT to donate blood in an effort to be tested, because while they DO test for at least 18 communicable diseases, the possibility of getting a 'false positive' is real; in that event, they will notify you to see your health care professional (who will do alternate, and more expensive testing to make sure it IS a false positve) while the blood bank will simply destroy the unit.
Take care