For curiosity's sake... I contact Canon CPS about the replacement cost of the front element on a 300L II... Especially because this is no longer just a "protective" element.
I got a reply and the cost for a new front element is approximately $600, give or take depending on any other damage or other things they come across with inspection of the lens.
Not really that bad considering... With a 30% CPS Gold discount, around $400-450 to replace it. I expected worse honestly! So there you go if you were curious about it like I was, in case something happens (hopefully not) to crack, chip or scratch that large front element!