If by 'Dupont' you mean 0.64mm square:
SKS (formerly Hirschmann)
They have Jumpers of about 20cm and 1m leads with 4mm at one side.
They also sell the contacts (with shroud) which take a larger wire than most. You can crim 0.25mm³ silicone test lead wire to them. If you look through my older posts, somewhere there's more info.