Just some information for you:
The ingredient in Primatene is ephedrine HCl. Another drug, Bronkaid, contains ephedrine sulfate. This slightly differs in the ephedrine HCl that you mentioned --- the molecule that the ephedrine is bonded to to stabilize it is a bit heavier with sulfate than it is with HCl. In theory, you get less ephedrine with sulfate than HCl, however, this difference is entirely negligible. On a milligram to milligram basis, they are effectively the same. Therefore, if you are looking for ephedrine, don't worry if it is ephedrine HCl or ephedrine sulfate.
Ephedrine HCl/sulfate is the isolated compound from the ephedra plant. Because the active ingredient is isolated, one's doses can be more safely titrated than if taken from the plant --- there is no way of eyeballing how much active ingredient is in the plant. This is the distinction between using the ephedra plant and ephedrine HCl/sulfate.
I'm not sure why you are having trouble finding Primatene --- basically all drug stores have them. Regardless, the drug Bronkaid contains 25mg of ephedrine sulfate per serving. Primate contains 12.5mg of ephedrine HCl-- you have to take two Primatenes for every Bronkaid.
Perhaps you should check out Walgreens, CVS, Duane Reade. Basically any local drug store for Bronkaid --- it's something like $12 for a box of 60.