how to hide this

[worthchanging]

I have this space/hole above recently(ish) installed boiler which I am not very sure how to decorate away.

I'm thinking some kind of curved plastic sheet in a kind of L-shape, from top of boiler to ceiling. But don't think I've come across such a thing at B&Q etc. I am quite a basic DIYer so perhaps it would seem easy to someone, but not me.
What to get, where from, how to use?
Many thanks!

 

[ktuludays]

http://www.pendock.co.uk/pipe-casings/boiler-pipe-casings/

 

[worthchanging]

http://www.pendock.co.uk/pipe-casings/boiler-pipe-casings/

thanks - that helps!

if anyone has other ideas, please post them