Hi Peter
From Bilston go down the New Road towards Brumijum until you reach the end where the New Road meets Hagley Road. Just across the junction is
Chichester Caravans and that's the nearest Lunar dealership to you. That branch of Chichester are also Bailey stockists so if you have a wander around their forecourt you will be able to compare both makes.
If I were you I'd just have a general look around to start with, don't mention the amount that you have available to the salesman but look inside the caravans to find out which caravan suits the needs of your family.
Another reputable dealership if you fancy a nice ride out for a Sunday are
Broad Lane Leisure who are a wee bit further out, their nearest branch is at Alcester off the M42.
Broad Lane are Lunar, Swift Group,Bailey, Elddis and Coachman dealers so there will be plenty of makes to compare, see which one grabs you the most when you find a caravan to fit the bill.
Good Luck with the search Peter, I'll forward my email address so that you can contact me if you need to.