Thanks very much Emile I will contact the seller today for more details.
Regards Mark K
Have look at this link: WW2 coiffe intérieur casque Adrian 1926 HELMET LINER 57 | eBay
I sent him a message and asked if he makes them in large sizes 61 - 62
my helmet is the biggest size and I also wear a large size 61 , they do look nicely made