Sleep Annexe for Apache Awning

(Moved from General Chat)

Hello there. Can anyone advise me on purchase of a sleep annexe or tall annexe for an Apache Verona Awning. We have just bought a 1997 caravan (first caravan for myself, husband and two little girls) and it has come with an awning but need more sleep space. Can I simply buy a sleep annexe or tall annexe for any Apache awnings of any age or would it need to be for an Apache Verona specifically. I have seen one for sale on Ebay but it is just a tall annexe for an Apache awning? Thank you for any thoughts.

Gladport