Nehi grape soda is available at stores like Lehman's and Blooms and Candy. These stores sell either by the bottle or by the case, and it is available both in-store and online as of November 2015.
Lehman's is an online store that sells Nehi grape soda by the case only. The soda comes in a case of 24 glass bottles. Each of the bottles is 12 ounces. As with all Nehi sodas, the grape soda has no caffeine and is made in the U.S. Lehman's sells other Nehi sodas by the case as well, but the store does not mix and match cases.
Blooms and Candy sells different types of old-fashioned sodas and treats, including Nehi grape soda. This store only sells the soda by the bottle.