Hi Sreenu,
I just can give my experience on this situation.
For instruments which will be shown before registration in a demo purpose, we generally put a simple label on which it's written : "Demo instrument, Not for sale" or " Demo instrument, do not use in a medical context".
For demo implants , we grave with laser on them the following sentence "Do not implant".
However, for demo instruments and implants, we generally have to declare them at the Customs office.
hope my little experince will help you
regards