Go on to figleaves website they have some really good ones. Be warned they are not cheap!! I like shock absorbers and another good one is Triaction by triumph. I am a larger lady in thet area so need lots of support....if you know what I mean!!
If you put in your size it'll show you the effect of riding. If you want to keep dropping those pencils you may wish to consider one? Breasts are only supported by your pectoral muscles so any stretching of the tissues (gravity, bouncy trot etc) will - eventually - have an affect on your *ahem* 'position'.