Well against my better judgement we went into Debenhams saturday and saw some blue 'speedo; sea shoes, expensive to the £3 we paid last time, but were a tenner each. We decided to get them as they had water holes in, and because they will be dry as soon as we hit the beach. The ones we got last time were good, but never dried out, hense leaving our feet sore.
Also soccer world in Lincoln has sea shoes - 75% off - selling at £2.99...wasnt my size, but i suspect other shops in other towns/cities will have them. Peacocks and PRIMARK only have flip flops at present.