Has your mum said you can have a run ?
CAn you give us more information.
Is this to attatch to the current hutch you have>
What size is the hutch you are planning to use for all 3 rabbits once they are bonded together?
Are you planning to get a totally new set up for the 3 rabbits
What sort of budget have you to spend?
By answering the above questions this will help us to point you to an appropriate run for the 3 rabbits
http://cgi.ebay.co.uk/MASSIVE-RABBI...et_Supplies_Small_Animals&hash=item35b2376523
dont know if there any good?