Hello Ian and welcome to the RV forum..
I don’t know builders in your area however vans originally supplied me with a list UK of builders that I found really useful. It may be worth asking vans for this List I guarantee that someone will be building close to you.
If you need to ask any specific questions or advice there are plenty of us who have built already that will be able to help you, all you need to do is ask.
Best regards
Mark