Research details at London based Universities

I need a list of the contact details for all London base universities (under 50) to include:

https://www.studylondon.ac.uk/universities

- Details of main offices
- Details of Student Union (SU) with Officers/titles/email
- Identification of contacts at SU with responsibility for Sustainability
- Identification of pages relating to clothes swapping or similar
- Identification of events calendar and in particular swap shops or clothes swapping

The main focus is I want to know what Swap events have happened and will be happening in 2020 and also who is organising them and/or responsible for sustainability. To include any societies.