It took us a while, but we finally sourced these hammered silver adjustable at a very good price. You can search Adjustable to see the whole range.
These do come in different sizes, the measurement when the 2 stones line up, which is thoughtful because if you stretch any ring too much it will ultimately break. This way you can choose ring closest to your finger size and adjust it to a perfect fit.
Size 5 covers the range 4 to 8. Size 6 covers 5 to 9. Size 7 covers 5 to 10.
Size 8 covers 5 to 11. Size 9 covers 6 to 12. These are all US sizes.
The stones are approx 6 mm round and 6x7 mm oval and weight is approx 5 gm. You might not get the actual ring pictured but the quality is very consistent.