A RNAV (RNP) Rwy 13 procedure does exist at JFK which does a beatiful approach to a 519 ft MDA.
The procedure is charted, at least I have it, and it was used for a while in VMC conditions, however, it is not currently approved for use, VMC or IMC. Wish I knew what the holdup was, but I do not.
In the bus, to get vertical guidance, one can select the rwy then select direct to rwy, which will show the "chinese G/S" or "donut". Works pretty well. Of course, it will take out the missed approach, however, that brings up the question of what missed approach would be, if given the visual
However, back to your point, currently, 800ft is the decison height on the VOR 13 approach, one must proceed visually from there, VASI has been provided for your convenience
