First of all, this refill is for XiaoMi Silver/Gold Metal pen, not for the plastic white pen.
I've asked GB rep for a metal pen refill, she has kindly allocated 100 pcs with coupon code AUjayzeeRefill06, it brings down the price to US$1.29. However for whatever strange reason, GB can only ship those Oil/Gel products through registered post, which takes FOREVER to arrive, expect 6 weeks postage time, and costs A$2.84, and there is no other way to bring down the postage if you only purchase this product alone.
After trying many combinations purchases, I found out that if you order 2 packs of metal pen refill, then order one pack of plastic white pen refill together, it would bring down the postage to A$0.34, so total A$5.94 for 2 packs of metal pen refill and 1 pack of plastic white pen refill, which is the best economical way for this order. You still need to use coupon code.
Here is the link for plastic white pen refill
https://www.gearbest.com/pen-pencils/pp_604496.html
If you don't have a metal pen, try this deal, this deal might still work, but you need to order separately from above deal.
https://www.ozbargain.com.au/node/339217
Use Paypal for your protection, and remember it TAKES FOREVER to arrive via registered mail, but it will come
Thanks OP! The metal refills are much smoother and less scratchy than the plastic (have been through 4 of the metal and 8 of the plastic so far).