We mostly use an liocal independent shop who are a big Clarks stockist but also do Start-rite and others.
Canvass Doodles or the like are a good bet for summer months as they work out under £30.
We have also in the past had feet measured and then gone to an utlet type shop or even ebay to get something similar.
On the whole I think it’s worth getting the shoes spot on particularly in the younger years as much for the peace of mind as anything having said that not everyone can afford to do this.
If it’s a case of being able to pay the high cost for properly fitted shoes but hoping to find a better deal then jsut do it right.
If money is tight full stop then explore the alterantives as far as you can.