cup of 25 pdr???

[toolong]

I have included pictures of item I have, could this be a cup from the 25 pdr?

The dimensions are
Hight about 36 mm
External diameter 90 on the widest part and about 85mm on the smallest.
There is atissue strap inside the cup fixed with glue and a metallic stapler.
In side the following text is written
CD N 27
dated 1944

 

[Falcon]

I believe that is the closure cup for the 25 Pounder. Quatermass posted a drawing of a complete round in the cartridges section. Are there and more of these cups available?