If you're looking for something in between pricewise, why not consider these Asos Heeled Sandals. While the price is very reasonable, this piece is an easy wardrobe update. You might also want to look at these Asos Lace-up Ankle Boots. It's an attractive option both price and quality-wise.
If you're in a Treat Yo' Self mood, then what you're looking for is these Asos Plimsolls. It's more expensive but worth your money.