How to change the Clone Stamp's source location with ExtendScript?

When using the Clone Stamp Tool, if you press `option + shift + arrow key`, it will move the sample point over by a pixel in the direction specified by the arrow key. I use this feature a lot in my line of work, and I'd like to reassign this shortcut to another set of keys that are easier to press with one hand.

This functionality is not accessible from the `Edit > Keyboard Shortcuts` menu, and it isn't recordable with Actions.

The easiest way I can think of doing this is by using a script that changes the location of the clone source, and assigning it to my desired keyboard shortcuts. Does anyone who's more familiar with ExtendScript know how I can change the location of the sampling point for the Clone Stamp Tool?