Sounds like a question for the folks from Cannon… but i will try and help anyways.
Let’s see; the Cannon web site lists the CannonLink as part number 1903040
The Humminbird web site also now lists it with the same part number. The 406930-1 part number was the part number that Humminbird used when we built and marketed the CannonLink. That is now being done by Cannon, so I don’t know if there were any changes to it or not but either part number should work.