Toilet box with panel and access

Looking for a carpenter or experienced handyman to supply and fit custom boxing behind a toilet in SE1 2DU. The toilet sits at an angle, leaving an awkward gap behind it. I’d like this enclosed neatly with plain white panels and a shaped shelf on top, similar to the attached reference image. Requirements: * Materials suitable for a humid bathroom, with moisture-resistant surfaces and properly sealed cut edges and joints. * Secure supporting frame and a neat, easy-to-clean finish. * Removable panel or top for access to the plumbing and isolation valve. * Keep the flush button accessible and allow the cistern lid to be removed for maintenance. * Measure on site and fit around the existing toilet and pipework. Please send your availability and a quote including materials, labour and finishing. Photos of similar work would be appreciated. Thanks, Riccardo