Why are you trying to get more electrolytes?
Electrolytes are mostly salt with minor added stuff so if you can find a way to get more sodium you will replace electolytes. The Power brand gels seem to have more sodium than other gel brands and Clif makes a Margarita blok with extra sodium.
A running or triathlon store will sell electrolyte tablets that you can use instead of gatorade or any of the high-calorie drinks. A couple of brands are Nuun and Thermalyte. Be sure to drink plenty of water with these. A running store might be able to give you more options as well.