you just need different layouts to print, not multiple records
layout 1 > Box 1 of 3
layout 2 > Box 2 of 3
layout 3 > Box 3 of 3
and in the script to print just select the first layout and then print, then the second layout and print and so on.
Or you can set up a special "print table". The print table won't store any data, except for an ID that matches to a specific record in your current table:
Orders::__pkOrderID = Labels::_fkOrderID
with that relationship, if you need 3 labels for for an order where __pkOrderID = 23, you create 3 records in Labels with _fkOrderID = 23. You can then set up your layout for printing labels based on the Labels table, but you can include any fields from Orders that have data you want to see on the label.
And there are a number of ways to get the "1 of 3", "2 of 3", etc info onto these labels depending on whether you print them for just one order at a time or print them for multiple orders at the same time.