When my fiance proposed to me he gave me a bridal set but I just wear the single part not the set. Anyway after some complications that I really don't want to go in to we cannot get the rest of my ring. I just have the single ring and I was wondering if I (A) need a wedding band or (B) where I could possibly get one. The ring I got is pictured below.
By the look of the ring, it looks as if you have both rings already. If this really isn't the case, you don't absolutely need another one. It isn't a legal or religious necessity. The ring you have could be blessed.
If you decide that you want a band, you could probably find one at a reputable jeweler.