Might be time to buy some Simms
I don't know your budget but this might be worth a go.
http://flyfishcalgary.com/board/index.php?showtopic=13489
My last two pairs have been Simms and I'll never go back!!! The pair I'm using now need a patch (Thanks Uber+barbed wire) but I'm sure they will last one more season. (3 on them now)