toys for playmat?

[skgnome]

DD has a playmat with arches on top which she really enjoys, however the arches have some loops to put some toys, the mat came with some toys but I'm struggling to find new things to put there to keep her entretained, anyone has suggestions on what to put? or where can I get some extra toys?

she's 4 months old

I found things with mirrors or rattles were good, I had a mat and bouncy chair with different toys, so I used to swap them around for a bit of variety.

I also had a black and white book which had a velcro strap, so sometimes I'd put that onto the arch as well.