Does anyone recognise this light cover?

[TullioK]

I'm trying to track down a replacement for a ceiling light I believe was originally fitted to my bathroom in the late 90s.

There are two lights but the cover from one is missing and I've had no luck in sourcing a replacement. The diameter is 30cm and here are a couple of photos:

Thanks in advance

 

[securespark]

Have you got a manufacturer's name on the fitting or any model numbers?

 

[TullioK]

I hadn't noticed it before but yes, the fitting says Illuma dl3td2161, I've now found one reference to an out of date Ebay listing which looked promising