Shoes from clarks think the last pair coat £45.00. They are holding up really well considering my 4 year old boy is actively trying to destroy them. Also got his plimsolls he uses for PE from clarks something like £10-12.
Very cheap shoes are very cheap for a reason. My wife used to buy cheap pumps at like 4 quid a pair claiming they where good value as they were cheap. Baring in mind some of them only lasted half a dozen wears before needing to be binned, she soon stopped buying them.
Shirts from marks and spencer which seem really good quality and come with neat little touches like Velcro instead of a top button making them easier for little ones to get dressed. Only £5-6 for a pack of two.
Trousers again I think come from marks and spencer and again not expensive.
We do have to get the school jumper, tie and PE kit directly from the school, but again the school aren't overly expensive. £13.00 a jumper, £2.50 a tie and £5-6 for the PE tshirt and shorts.
I remember the days of my mum complaining that my school blazer could only be purchased from one shop in the area and you had to go and get fitted and you had to wait 6-8 weeks and it cost £70.00 a go.