This July, Japanese peripheral maker Hori is releasing a Joy-Con with a proper D-pad. Thank goodness for that! You will, however, have to trade some standard features for it.
The current left Joy-Con features face buttons as does the right one. But if you mostly play in handheld mode, a left-side D-pad might be more comfortable. Hence, why Hori is selling a left Joy-Con with a D-pad.
Note that it can only be used in the handheld mode and doesn't have acceleration, gyro sensor or vibration features.
According to 4Gamer, it's priced at 2,678 yen ($32.98), and there's currently no word of an international release.