I looked for a .450/.400 option in their dropdown listing, did not see one. If able to vote more than once I'm going back to see if they have a .35 Whelen listed.

Something of note for anyone interested in the British calibres, a company in the USA, I believe the name of the company is Ballard Rifle & Cartridge, makes a custom High Wall in an "Express Rifle" version and calibres offered include .375 Flanged and .450/.400. The price is a bit high though.

Richard.