The chain's not supposed to be long enough for the wheel to sit all the way rearward. Ideally, for a bike like this, you'd want the longest chain that fits that requirement. You tension the chain after it's already on the sprockets by moving the wheel rearward in the dropouts, so just get a chain on there that lets you install the wheel.
As long as the wheel isn't right at the front of the dropouts, your "half-link short" chain should be ideal.