MS Word overwrite Paste Options:

[Aussiebear]

This means using VBA to change the default behaviour of MS Word on the client computer.
That feels invasive. (might be a genius work around, where nothing else will work)

Ideally I'm seeking a solution that only affects the document in question.

If someone knows how to inject code when the user chooses Paste Options: ... that would be very helpful

As Chas Kenyon has suggested it cannot be done. Further as you have intimated you are trying to change the default behaviour on a client computer and that IS invasive.