Sure, there are plenty of older road frames with horizontal dropouts; if you are lucky to find one in your size and of the quality you're interested in. If the OP wants to go new, there's the Surly Cross Check, Salsa Casseroll and probably a couple others I can't think of right now. Both of those are fine frames, but not AS cheap or available as frames with vertical drops.
What is the spacing of the hub you're interested in? If it's 130mm or less, you'll be fine squeezing it into the 120mm spaced rear end of your fixed frame (or cold setting if it's steel) but then you'd only have one bike when you could have two!
Those EBBs look neat, I wonder how the hold up over time. The downside, I guess, is you're limited by what cranks you can use.