Rabbit Shelter

I'm looking for a rabbit shelter for my 8ft by 6ft run.

I have already got the Trixie Natura Pet House for my 8ft by 4ft run but I'd like to get something longer. It can't be too tall as the rabbits enjoy sitting on top of it:lol:

Can anyone recommend anything:wave:

When i had outdoor runs I just bought a little hutch - you know the really inadequate ones that pet shops sell that are about 3' x 1' - and took the doors off