Yes I believe you can just purchase the lid separately.
Not very much. When empty I can toss it around very easily. It is made of polypropelyne which is light yet strong. Maybe twice the weight of a dodgeball.
I think so. If you was storing dry products like cans or rice.
I measured it out...height 18 1/2 "inches........length 2' feet from handle to handle ....width 15 3/4" from side to side
I had two covers crack when they got cold. Would not recommend for outdoor storage.