I would use a hidden text object but only fill it with text up to and including the space before the word you're interested in. Use the text width property (not the text object width) and add it to the text object's bounding box left position. That will give you the starting/left x position. You could also measure the width of a single word using a similar technique. Just note that it takes one tick for these text width values to populate after signing the text content.