Apple tree advice needed

I have some questions regarding an apple 'scrumptious' tree (M26) that I need to keep in a pot. 
1. What size /type of pot would be best for it? I need something that won't blow over in wind. I have found a teak planter L45xB45xH90cm and wonder if that would be suitable.
2. Can anyone recommend a place that sells affordable large, outdoor pots?
3. I also would like to prune off the lower right branch. Can I do that now in summer?

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Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
http://stewart-garden.co.uk/products/gun-metal/50cm/smithy-patio-tub/
The cylindrical shape is stable and the plastic ensures less reliance on constant watering. You may have to drill holes in the bottom of the pot, if they aren’t already punched out, I can’t remember.
The large size, 66 litres, 50 cm diameter, is suitable for trees grafted onto dwarfing rootstocks.
Any tree grafted onto larger rootstock will not do well in the long run.
I wouldn’t remove the entire branch. Leave about a foot length. It’s never going to take over the tree in any case and by leaving a bit you encourage flower buds.
If you live in Derbyshire, as I do.