[reefskinner]

Strange, no US sellers list anything even close. I did a Google search and found that the BL-4c is rated at either 720 or 750, depending on the site. The Bl-5c is rated at ~ 850, but is around 1mm thicker. I wonder if the 5c would fit?
I see the 4c on ebay from 550 to 750 and the 5c seems to go 700 to 900.

Thanks again