Phot-R 150cm (59.1") Octagon Octagonal Octabox Folding Umbrella Softbox Reflector and Grid with Bowens Mount Speedring and Elinchrom Adapter Photo Studio Strobe Flash for Flashguns and Speedlite: Amazon.co.uk: Electronics & Photo
Godox 80cm / 31.5in Portable Octagonal Umbrella Reflector Softbox with Bowens Mount for Flash Speedlite - Newegg.com
Rent Bowens BW4036 92cm/36" Silver / White Umbrella in London (rent for £3.00 / day, £1.43 / week)
Buy - Bowens BW1885 (BW-1885) 15cm Wide Angle 120 Degree Reflector with Umbrella Bracket and Silver Interior