Challenges with Data Merging into Placed InDesign Documents

Hey everyone, 

I have been diving into data merging with Indesign and absolutely loving it. Here is a catalog I created for the company I work for. I also have started to utilize separate .indd files to place pages from an indesign file into another indesign document. This has made my documents more editable in a helpful way.

I ran into some difficulty using data merge and placed documents. So, I am curious how some of you might approach this task with inDesign. 

In one .indd, I have laid out a hang tag for retail products. Image below

In another, I "placed" the hang tag on a 13x19 sheet for print. 

 I like this approach because when I edit the hang tag, it automatically updates all instances of it in my hang tag layout. However, I am not able to Data Merge to a placed document, AFAIK. And we have close to 500 product variants to create hang tags for, so Data Merge is absolutely necessary. 

I'm thinking I need to bite the bullet and simply recreate the layout grid of hang tags everytime I want to change the hang tag design. That way, I don't need to rely on a placed document and can data merge as I usually would. However, I am hoping someone else has another viable solution to share. Thank you for your time!

Noah

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