Metal. 1923

Looks like a contemporary decorative item.

 

i've heard about metal post cards...but don't know much about them.
still,,I think Roaring may be on to something as the post marks seem all over the place..

 

Try a company called "American Chateau" or go to your favourite search engine and look for images using search terms like "London England Metal Postcard Big Ben" or "New York postcard Statue of Liberty metal".

The www.americanchateau.com website is down at the moment (or won't let me in from an IP address in the EU). I really don't think I'm missing much.

 

Said "currently down due to maintenance." Should be available again shortly.!

 

That certainly looks like the publisher of the postcard in the photo used for the NYC 'nostalgia' item, INH. But it's impossible to be know what has been removed from or added to the image (apart from "New York" in the same style and font as "London" on the first item).

Finding the original postcard wouldn't greatly help OP, but it would probably be worth more than the items posted above.

I've seen similar wall decorations on sale for $14.99 for a set of three (London - Paris - New York). That's full retail, of course.