My 11 year old has worn Dr Puri (small) from kmact.com with this. It (177x67mm) is bigger than Bluna facefit kids (160x66mm) or blue tiger(155x70x130). kmact.com have 2-day shipping option with ($). They are based out of houston.

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If you have korean stores (hmart etc. ) in your area you should be able to get KF94 of different brands.

Lowes has N95 (NIOSH) which tends to run ted smaller (No first hand experience but read it online).You can pick it tomorrow in-store depending on where you live.