@ptaylorboyd- Welcome to Mayo Clinic Connect. I'm glad that you found us. I don't have a sodium deficiency that is bad enough to warrant taking extra salt. However, I'm glad that you asked this question because if I need it I know where to look. I can't recommend any particular one but if you google electrolyte water WITHOUT SULFATES/SULFITES you will find some.

I just found this: Another possible cause for SOB! The ER doctor did well by you! I really hope that it works for you.
http://chemocare.com/chemotherapy/side-effects/hyponatremia-low-sodium.aspx
Did your doctor tell you how much sodium and in what form to take?