Surely it wouldn't suit an allotment - far too smart. Can't you rustle something up with a bit of old timber, sacking cloth and discarded window frames?
Fascinating - never knew there was such a thing. And I see there;s even a 'Gazebo with Portico'. https://www.aldi.co.uk/adventuridge-gazebo-with-portico/p/016931383547001 The 'Portico' is what I would generally call a 'tent'!