Will Royal Mail tracking or Canada Post tracking tell me if the item is in customs?

I ordered an item about a month ago now. I'm using Royal Mail international signed, which includes tracking. The last thing that the Royal Mail tracking site shows is that the item "has been passed to the over seas delivery service". A website called track it online tells me that the item has left the postal office and is on its way to Toronto, Canada (I live in Ontario) but that the tracking number is not registered in the postal data base of Canada Post, yet.
The item was expected to be delivered in 5-7 business days (UK - Canada) so I suspect that it's stuck in Canadian customs. The reason I'm worried is that there is no indication on tracking that it is in customs. I don't know where this item is right now! Is this okay, and is there any way I can check?
The item is a pair of Halloween contact lenses if that makes a difference.
Thank you in advance!

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