I've been meaning to ask if you have ever considered left-handed cutting boards? I do quite a lot of patchwork & the most popular suppliers of materials looked at me as if I was mad when I enquired at a large patchwork event. They told me just to turn the board around! This doesn't work as one side is shown in inches & the other in centimetres, both going from left to right. (I hope this makes sense – you might like to try it out on an old envelope!). I usually just subtract e.g. 18″ – 7″ = 11″, but it would be much easier with a left-handed board! I would imagine other left-handed quilters & craftspeople would be glad of this too.
ALH: We have not come across anything like this – we had to have our own left-handed rulers made with the scales going form right to left and I guess this is something that would need to be custom-made as well. This normally requires a large volume (minimum for our rulers is 2,000 of each size at a time) so is not easy for specialist products like your cutting board.
We'll keep a look out and if anyone knows of a source for these please add a comment to this post.