How did the brake perform?
I've just bought a 300wby with the Accubrake fitted, I'd guess it reduces recoil by 45-50%, I'd rate the recoil somewhere between a 243 & 7mm08.
I'm pretty sure you can get your gun shop to order them through Nioa Australia & get your local smith to fit it.
Mate just contact Shawn and get the 4 port DE break i did .
Being fitted at the moment to my 28inch lilija barrel .