Playmat dilemma.......?

Hi, I can't seem to find a large soft (maybe quilted) playmat for my 6 month old that is not too expensive. Everywhere I look, it seems I'd need to pay at least 30 pounds. I'm wondering if I could buy a baby's cot quilt to use as a playmat instead. Would it be soft and safe enough for my baby to play on with hard floor underneath it? Thanks for help....