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Considering dry ice sublimates at -78°C, this is likely to cause cracks or other damage to the equipment being shipped.

> Use two tiny needles

I'm wondering if it would be possible to manufacture some sort of clear plastic sandwich-like material that contains two separate chemical "fillings", kept apart by a central barrier which, if punctured, would allow the chemicals to mix together, triggering a colour-changing chemical reaction.

I guess the problem would be wrapping the target object in a way that couldn't just be unwrapped afterwards, but maybe a glue could be used which creates a chemical bond that is tamper-evident.

That's basically how Polaroid pictures work(ed). The developer/fixer was in the bottom edge, and this container was punctured and the chemicals squeezed out by the rollers as it came out. The only thing left would be to distribute it along the back of the photograph, so you, you know, shake it.

Cold (un)pack.