Please help me date my fireplace

[Hmmph]

We have recently moved house and have a fireplace in the lounge.
I am trying to work out if it is original or not.

Anyone good at dating fireplaces?

I am deliberately not revealing the age of the house...

The claygate catalogue has brick sizes in the catalogue so that would give you an idea of whether they match. But I think they were in operation for much of the early part of the 20th century, so e.g. we have one that almost certainly is original and one that definitely isn’t because we know about some structural changes affecting that part of the house from the mid century.