Now that the new 3DS XL has been announced, Nintendo has wasted little time in launching an official website in Japan. Interestingly, Japan has red + black and silver + black models, like Europe and North America, but doesn't have the blue + black version, opting instead for an all-white console.
The all-white version is the only model that we've seen so far with a consistent colour on the exterior and interior, and does look rather nice. As reported by Andriasang, the system will have a recommended price of ¥18,900, which is just over £150 at the time of writing. If you make a direct comparison, that means the Japanese price is higher than in the U.S., but that doesn't necessarily take into account sales tax in some states.
As for UK pricing, it seems to be the case that Nintendo is yet to confirm the wholesale cost to retailers, so any prices that are currently listed are likely to be pure speculation. Until more major retailers declare a solid price, we'll wait and see.