To do this natively in ID you need 250 different back pages, and most likley this means 250 documents, unless you send it to a printer who can do VDP (variable data printing) and merge the numbers during output.
If you are sending this out to be printed, ask your print provider if they offer variable data printing. You can have the numbers printed from an excel list just as you would for addresses on a mail piece.
You could also choose to use mail merge in Microsoft Word, to do something similar.
Those are probably the least expensive options, the best options require software. Maybe there is a plug-in that could help.
Thank you so much! Good suggestion!
They have the capability to do variable data! I'm good! Thanks!