Electabuzz works fine but not efficient and will be a potion/revive hog. I have 3 (1150cp-1300CP) I use for prestiging) but they aren't as tanky or as good as a Jolteon. You will just end up going through more potions, even with a powered up Buzz.
Wish I could trade you some of my Jolteons for some Vapes. I had the opposite problem for the longest time. Couldn't get a Vaporeon. I had a streak of 6 Eevees in a row ended up as Jolteons.
I honestly wouldn't waste dust powering up an Electabuzz unless they get buffed at some point.
At level 30 a good Electabuzz will be around 1850CP where as a Jolteon will be around 2300CP. Jolteons have more defense and a higher attack stat so will get through the Gary's quicker and more efficient.