This is actually the original antique mortise hardware - it is an antique unlacquered brass. These can be found at architectural salvage specialists or on ebay, but you will need a carpenter with experience - and door slabs in good condition - to install them. There are modern day reproductions via various sources on the internet.

Hey there!
Nostalgic Warehouse sells hardware with the same style, with updated hardware.
It holds better, suits antique decors just right and is sometimes more affordable than restoration. As for the color, as Studio H mentioned, in these days unlacquered brass was a common finish. Today, you could go with unlacquered brass (But be aware that it'll start bright polished brass), or antique brass from some manufacturers, such as Nostalgic Warehouse.
You can view those models on their website here
We distribute their products in Canada, but surely there is a local distributor near you that could help you with their products.
Have a great day!

Thank you both so very much. Your information is very helpful. And I also appreciate how quickly you responded. I apologize for my late response.