If you have the old style metal wipers, you can get flat blade replacements on ebay for much cheapness. They are much better, quieter and smoother, no chatter, and they last longer as there is constant pressure along the blade, rather than the pressure points caused by the metal type.
I’ve changed to the flat type on my last three cars. I have seen them in a couple of Tesco’s as well.
Just watch out if you have wiper mounted washer tubes, when I bought my van blades there was only one seller that sold them with washers attached.