Looks neat! I found a 9pcs 37-82mm step ring set at eBay and it is only $5 (free shipping from China).
When they are stacked, are they heavy?
I never thought of them as heavy but heavy is a very relative term. Looked up my order on amazon for the rings I purchased and it listed the shipping weight at 2.9 oz, if you want actual weight PM me and I'll weight them when I get home. Your set has the same step rings so I'm assuming they will be identical except for the brand name.