Redan Place is located alongside Whiteleys Shopping Centre in London's Bayswater.
Number 23 is tucked away at the end of the short road. The building currently occupying the site looks rather modern so its unlikely that this is the exact same building that Marvel occupied. Bah. But, nevertheless, here's a couple of hastily snapped snaps to give you an idea.
The Whiteleys connection almost ended in tears. As mentioned in our Arundel House rundown, a crane that was converting the former department store into its current incarnation toppled and narrowly missed demolishing Number 23. Fortunately no-one from Marvel was hurt. The Whiteleys entry on Wikipedia suggests several people were killed in the accident but this has proven hard to confirm online.
* M-UK seem to have been dual running offices for a while. Late 1982 issues use Redan Place as the mailing address for offers but still use Jadwin House as the editorial address and for readers correspondence.