It's an adpator for a suppressor. Not something you need to worry about in Canada.
In any case, they don't ship here because it's made for an M14. M14 parts are restricted for export and the manufacturer requires an expensive exporter's licence.
$129US isn't ugly considering it's machined.
Perhaps NEA will make one and hook you up
It's in the queue and included in the 2011 price list sent to dealers, pictures and all