Welcome to the forum. If you're located in the UK then both The Whisky Exchange and RMW both have the two single casks listed on Lark's website - at very similar prices.
But yes they are on the pricey side, i hear it's boom time in Oz and they're all sat on piles of cash and nothing is cheap anymore LoL. Maybe that's the reason. I can't say much about the quality of the whisky, i have been told Lark isn't great, but they are winning awards and fans. Dramtastic has tried them and may look in and advise on which is the better buy.