Roches Stores used to do them some years ago but not sure if they still sell them.
Argos have but it is probably too clear and does not hide a fireplace. Same probably applies to these ones:
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They are probably clear from a practical 'keep an eye on loose fuel' perspective.
I bought one some years ago in Karl's Furniture in Ballyfermot but I'm not sure if they still sell them. Suppose you could try some of the fireplace shops but if they are selling good fireplaces why would they sell screens to cover them up
I saw some nice simple one in Woodies at the weekend. Also I saw some nice fireside accessories in our local old fasioned hardware store.
For fire guards, go for the finemesh if you are buring smokeless coal or timeber blocks which are inclined to spark. Also make sure that as much of the open fireplace is covered as possible.
If you have small children you may need a second coarse mesh guard which can be anchored to the wall.