Add numbers at end of staves? For rounds singing

I notate a lot of rounds/catches/canons and sometimes I want to show the staff number the singer should jump to at the end of the line. Here's an example of the format I want:

Credit: The Penguin Book of Rounds by Rosemary Cass-Beggs

I know that the initial numbers can be created using Instrument names. Is there a way to create the number at the end of each staff?

Thanks!