I have searched in vain for the same sort of thing.I had a couple of pairs in lycra which I bought in Marks in Tooting .Quite a few years ago now though.They are ideal for me with boots or wellies for dog walking in the winter.They don't ruck up like normal trousers or jeansand stay put with the elastic under the foot and....they are warm!
I scoured London for them and now we haved moved to Norfolk I have scoured round here to no avail.When I have asked in various shops I have been told they are no longer "fashionable".I prefer a straight or narrow leg trouser.These boot cut things do nothing for me.I hate trousers that flap in the wind so to speak.Sorry I can't help you to find any .I think we will have to wait until they come into fashion again!!