This gives a new meaning to unarmed attack, but doesn't seem particularly useful.
First, the unarmed strike:
When you make a weapon attack such as a melee basic attack, you can use the monk unarmed strike, which is a weapon in the unarmed weapon group. This weapon has the off-hand weapon property and a +3 proficiency bonus, and it deals 1d8 damage. You must have a hand free to use your monk unarmed strike,
Hurl Weapon states:
You can use any one-handed off-hand weapon as a heavy thrown weapon
Therefore, all a monk needs to do is amputate their hands, and they can indeed chuck them at an enemy as heavy thrown weapons. There is no provision for "ranged unarmed hands-less ki attacks" though. Perhaps the monk should invest in increasing her reach instead.
On a more serious note, however, there are no restrictions on refluffing thrown shuriken (or what have you) to be "ki bolts" if it fits the character's style. Also appropriate would be a transcendent ki focus proficiency.