Only just seen this topic so apologies for late reply.
The lovely 0-6-0 posted by LNWR modeller looks like a London Road Models J3 (larger boiler than GNR J4). These kits were designed by George Norton and are a bit dated. The 0 gauge version now marketed by Gladiator is a first rate kit. The livery in the picture is correct unlike that of the Class C 4-4-0 below it. One batch of Class C locos had light brown wheels but none had light coloured tender frames.
The 4-4-0Ts were by Jidenco/Falcon Brass.
There is another J3/4 (M&GN Class Da) available from Ace Models (William Ascough). There may soon be a M&GN Class A 4-4-2 tank available from Ace and promises to be a very good kit without the issues associated with the J3/4
The 3130 class Midland locos had smaller wheels than the M&GN D Class but it is not too difficult to create a M&GN Class D from them. These kits were also designed by George Norton.
The Alan Gibson 2F can be made into a M&GN Class D and the 3F can be made into a Class D rebuilt with G7 boiler.
Full info on M&GN locos is available in Bob Essery's book on the M&GN and its Locos (Lightmoor)
John Hobden, M&GN Circle