My mother is against menstrual cups!

Hello! I'm new to this community, but I have been reading random posts for quite a while, and have known about mestrual cups for about a year.

Anyway, I'm having a hard time convincing my mother to let me get a menstrual cup. It's not the issue of money. I told her that I would pay for it using my savings, it costs about S$50 here. She is just turned off by the idea of sticking something up there, so when I told her that it's actually safe, she didn't want to believe me. She asked why they don't sell it everywhere like they sell pads and tampons if it's so good. How am I supposed to answer that?

I live in Singapore, which is in Asia, so the people here are very conservative. To my knowledge, people rarely even use tampons. Pads are more common. And it's rare to hear people talk openly about periods in big groups, but it does happen sometimes.

The only menstrual cup I can get here is a Mooncup(UK) and that's from an online shop based here. I'm really interested in both the Lunette and the Mooncup. Plus, I have no idea where my cervix is even after sticking my finger in there. Felt something about 1 cm in, but not sure if that's my cervix.

My main problem now is still convincing my mother. She told me that I can get one when I move out, which won't be for at least another 5 years.  She just tells me to stop talking when i even mention it, so attempting to explain the pros of cups hasn't been working so far.

Has anyone else had this problem of convincing your parents to let you buy a menstrual cup? Any suggestions on how I can approach her effectively? And does anyone know where  to get cups in Singapore (not online)?

Thank you for reading!