Every MOM I've been looking at sells at minimum 3.5 grams per strain. I remember before there were some sites that you could buy by the gram, wanted to know if they still exist
Budmail have gram options! ,and usually you can mail them If they don’t sell by grams and they can arrange an option for you, WTFCannabis did it for me. You can try to contact them on discord or something. I’m pretty sure they can offer you something.
Cheers