Hi AddMoreCloud,
For changing out the sidestone setting style, it would require a whole new mold to be done and thus gets into custom design, which we don't do.
You could contact WinkCZ.com who carries Asha and they do a lot of custom work, so you could talk to them about a similar design but with the carre or similar side stones.
Also, RingExplorer.com will be available in about 2 weeks and you can use that to search for possible rings as well.
Hope that helps,
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