I dont know about best price but check with Don. He's a long time board sponsor and Merc guy. He's a 1 stop shop and will make sure you have all parts needed.
My boat shows this info on my Lowerance Ti 2 is the vessel view better ?
One plus to the Vessel View is you can designate a preferred dealer and if you have an issue that dealer can pull up your vessel view in the system and see the codes and alarms and give you some guidance without bringing it in maybe....