The 3 central pieces are Bullers made, while the 2 on the ends are not. Lets start with the NOT.

The left end is from India, but definitely not Bullers. The right end is a British made Taylor & Tunnicliffe 1920 for use in Norway. Please click on View Original for better detail

The 3 in the centre, starting centre left left are a Bullers made piece for Namibia, Africa [thanks to Robin Harrison] The centre piece purchased on eBay is Bullers made for FCCA [Ferro Caril Centrale Argentina] and the centre right is from Norway, but you can see the Bullers logo

Notice the similarity between the 2 pieces from Norway, small one by Bullers, larger by Taylor & Tunnicliffe