hi, i guess you'r talking over trousers?. yep gortex like these will do the trick http://www.ebay.co.uk/itm/British-Ar...05%26rk%3D3%26

i've be using a pair for the last two years commuting and offroading, with no probs.

as a guide i'm a 34 waist, my Hg cruise jeans are '52' the leggings are 85/96/112.
yeah a smaller size would do and the beauty is they pack small, don't let the jeans outer fabric to 'wet out' so a warmer ride

so all's good