From the official Tennmak store they have an 18pc (ie 9 pairs total; 3 of each color) pack with NO case, for like $8.
https://www.aliexpress.com/item/TEN...d-ear-tip-earphone-accessory/32808506339.html
With either that one, or the one with the $2 case you can specify ALL 1 size. So for example, if you only use S tips, you just send them a message and say ALL S. So you will receive 9 pairs of S tips. Or, if you use L and your significant other uses S, tell them you only want those 2 sizes. That's $0.89 per pair, and you don't waste any money on sizes you'll never use. Make sense?
The alternative is ONE set of KZ, with SML for ~$1.20. Well, in the example of you only using S tips, you basically paid $1.50 for 1 pair of tips because you can't use the M or L. And your 1 pair of S tips will fall apart in a few weeks, because the KZ Whirlwind tips are fragile pieces of junk.
The Tennmaks are significantly cheaper per pair, and they last 100xs longer than the KZ version.