Im not from new brunswick but I beleive this might help with your dispute. Just wanted to point out that if the package was insured, canada post can/will pay for the damages occured during shipping. This is done by the sender calling up canada post and making a damage claim.
This is one of the reasons I ship any guns/parts insured. the extra 2-3 $ is well worth the cost and if the buyer doesnt think so, the risk would be on them for not paying for the insurance. If you dont have it insured, I would highly recommend that you have insured all parcels to the approximate value of the package your shipping in the future.
Good luck with resolving this issue
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