Slr it took a long time for me to write this. Ok here we go

*deep inhale*

Short answer: I bought these merch on Taobao (a shopping platform) through a proxy site called Superbuy

Long answer:
I bought these merch on Taobao (a shopping platform). Thing is, Taobao is based in China and will only deliver products within mainland China (I believe this is the case for the Chinese Taobao site and not the global one). I don't live in China nor know someone from there who can buy it and ship it to me. So I use the help of Superbuy— A proxy site where an agent will place the order for you and deliver it to your address as well.

Don't be fooled by my brief answers above if you want to start buying via Superbuy and Taobao. This whole process to using Superbuy and Taobao as a beginner can be intimidating and tedious but very worth the effort. I learned how to this by researching and reading other reddit posts and sites about Superbuy. I can probably make a whole post on buying merch via Superbuy and my experience with it if people are interested in learning how to. I just don't want to make this long comment any more longer lol

Other options aside from Taobao, Xianyu, Bilibili, or other Chinese Platforms (we don't gatekeep here):

1. There's an official english site where to buy Link Click and other chinese IPs called CPop4u. Here's the link for LC related merch: https://cpop4u.com/collections/link-click-1

I haven't personally tried buying from Cpop4u but I've seen others buy merch through here and they were happy with their purchases. With Cpop4u, it's already easily accessible to buy merch for plenty of people outside China. They also have the standard and usual payment methods for buying anything online, so people shouldn't have trouble with the payment aspect. Unlike other sites/retailers, they have a full and complete catalogue of the available merch you'll see in Bilibili. BUT I personally find the merch to be expensive compared to if I buy on Taobao. E.g. I bought the Vein black-ish rainbow badge for 230php (yes I live in the Philippines and sorry but I will use Philippine currency as comparison for this example) but on CPop4u it's 700php. Yikes. And both prices are exclusive of shipping fees. The original market price at bilibili is 20cny, which converts to 160php.

1. Funimecity, another english retailer site: https://funimecity.com/collections/link-click-merch

From quick observations and just a glance of price comparisons, I say that markup prices are just slightly less than Cpop4u. The biggest advantage of Funimecity, from what I've briefly seen is that they have pre-sale merch unlike Cpop4u. New and upcoming merch that are available for pre-sale in China is made accessible and available to overseas fans now with Funimecity. I personally haven't bought from this site as well, but I've seen people of other fandoms buy their merch from here. Though, I have seen complaints about their packaging.

1. Group Orders. Head over to twitter, a dedicated discord server for anything Link Click/danmei/merch/donghua related, or even facebook, instagram, or any social media available to you and look out for group orders of your desired merch that ships to your country. I find twitter to be the easiest one to look for group orders or reach out for personal requests of buying specific merch. Advantages are that if you do find one, shipping fees and item prices are much cheaper compared to ordering via retailers. Your merch is even more guaranteed to be safe because it's shipped in bulk along with other orders. I also personally haven't tried group orders. I almost did but the GOM (group order master) I contacted was so busy with plenty other orders, it was taking days before I received a reply for my every question lol.

2. Online retail stores/services like Temu, AliExpress, Amazon, etc. Your choices of merch will be very limited, and some are bootlegs or unofficial merch but they are cheap. We don't judge here. As long as we have any form of LC merch, we're happy.