Within 20 miles of Salisbury I have found:
HiveStudios - Chandler's Ford Hampshire
Roundhouse Pictures, Unit 30 Southbrook Rd Southampton SO151GQ
Old Bakery Studio Whittle Road, ferndown.
I have not got a clue if they are any good or what sort of studio it is. It is also the only details I have got. you will have to find telephone and exact addresses by some more research.