Use your old workflow.
One can take of copy of the form you want the scripts and form fields from and replace the original page with the new page.
You can insert the old form into the new form and delete the old form, this will add all the document level scripts.
One can use and FDF to import document level scripts and other scripts.
Thank you gkaiseril for your suggestions. I've done both of your first two suggestions before in other forms.
I'm really looking for a scripted solution of some sort, if possible.
The issue with #1 is replacing pages will only bring over the layout graphics and nothing interactive on the new page, so that's not viable unless the update was something getting omitted.
#3: I've done a little with FDF data. The issue with a lot of the forms I do is that for some reason, FDF data will destroy my button icons, so I typically use it in text only forms. I'm not familiar with how to import scripts with it, however.