Used Cot mattresses x 3 (Dunstable LU6)

We are looking for 3 used 1 metre x 50 cm approx cot mattresses to use for a DIY project, and as I am told that many people replace cot mattresses, i wonder if anyone has any they would like to find a home for.? We are not in too much of a rush so do get back to me if you might have one soon. Thank you.