Go twin-wheel.
The wide spaced wheels let you push the barrow rather than fighting to keep it balanced on a single, central wheel, putting all the stress on your fulcrums of shoulders meeting spine and hips meeting spine.
Mine came from Homebase a couple of years ago, when they were still reasonable garden centre. Haemmerlin do a couple.
Go twin-wheel.
The wide spaced wheels let you push the barrow rather than fighting to keep it balanced on a single, central wheel, putting all the stress on your fulcrums of shoulders meeting spine and hips meeting spine.
Mine came from Homebase a couple of years ago, when they were still reasonable garden centre. Haemmerlin do a couple.