Could try Richa, I bought a pair of their monsoon trousers a few years back and they do a long leg, think it's about a 35", fits me OK. Found another very cheap brand so not sure on quality called texspeed (might be texpeed) did a 36" leg and was in the order of £50 to £60. Apart from premium brands only other I can think of could be Halvarssons Zen trousers, think they could do a 35" leg but are nearer the £300 mark.