My first instinct is to use custom shapes. Add the meteor to your custom shapes folder to replace mine.
Then create the axis using numbers (as you eluded to). In order to get stacked meteors like on your picture you will probably need to make a Y axis of some sort.
The size and distance is based on what you had posted in your question.
Attached is a workbook with the basic idea. You will have to play with the numbers and axis' though.
Hope this helps!
Meteor Graph.twbx 152.1 KB