Took some hunting to find the tree you referred to :-) Best to link directly to that thread......... But the tree in the photo is not going to match your preferences. It is not weeping, looks like it's much larger than 4-6 feet and is likely not a green leafed variety to be showing that much red in June when the photo was taken.

But there are several that would fit. Both Waterfall and Viridis are popular green weeping dissectums that offer great fall color and are readily available at most places that offer a range of JM's for sale. And certainly by mail order. These are sometimes sold interchangeably and in truth, they are very similar in appearance.

Height is quite variable with the weepers. If you want a low growing tree, you need to select one with a low graft but generally the growth habit of the weepers does keep them pretty low to the ground. But they have a strong tendency to develop some serious width over time so allow for the spread rather than rely on pruning to fit the space. And the best fall color will develop if the tree gets a decent amount of sun. Both selections are quite sun tolerant.

Acer palmatum 'Viridis' (Viridis Group)

Acer palmatum 'Waterfall'

Other green leafed weepers.