I bought hard side poly type luggage from ebags. My scuba gear fit perfectly. I use Scuba Pro twin jet fins and they fit in the checked bag. All of the rest of the gear plus my other stuff fit in the same bag. Even though my regulator has a case I like the hard sided luggage. I hosed the luggage out when I got home but there is still a bit of sand in there.
https://www.ebags.com/
The luggage is pretty light.
I took my lead weight in my checked bag. It was about 11 pounds. If you take lead be sure to have it in a separate case and tell tsa you have scuba lead as it shows up black on the xray and they can get wondering.
Bill