Fireplace renovation - not sure what would be a suitable surround?

[yesyeskatie]

Just moved into a lovely little cottage and would love to renovate this fireplace but not sure how to do it justice. Does anyone possibly have any advice on the surround? And are there perhaps other parts missing? The brick behind seems slightly odd...
Thanks so much for your help!

 

[Stevers]

Looks like a little Georgian bedroom fireplace that might have had a plain slate or cast iron surround, the fastenings at the top might help identify which type. It all looks in very good order including the neat brickwork, and some very pretty wallpaper! No skirtings though, which seems odd.