As Godzilla King of the Monsters hits cinema screens (seen it, very noisy and lots of fun) SH Monsterarts have confirmed they will be releasing two of the films protagonists as a webstore exclusive 2-pack.
Mothra and Rodan will arrive in November 2019 and pre-orders are open now at the Bandai webstore for 11,000 yen. Both figures will come with a Tamashii Stage Stand to allow them to be posed in flight poses.
The Bandai Spirits webstore does state International Shipping is available, but I can't quite work out if that means the UK or not and I don't trust Google Translate to give any more info. I'd suggest collectors outside of Japan may want to wait to check availability from their own distributors such as Bluefin.