I'm sure they're probably not proprietary Apple screws.. 😀
Are you really missing so many from the set?

Aren't they just stainless steel Torx screws?

They use different one. Well, maybe I need to check screw manual for that
https://www.ifixit.com/Document/446/.pdf
well, thanks, I will try to buy... but that guy who sold that iBook to me...was crazy.. because I ordered bottom case, because that was a problem with carving and many things just destroyed there. also many screws are not original and even doesn't fit well there? and some of them just missed!
But it was so cheap, so I can't complain. I will research which one I miss and probably find somewhere, just thought maybe you know some places

So yes, I missed at least 8 of them from that iBook 😒

http://www.ebay.com/itm/Apple-iBook-G3-Clamsh … FcAAOSwdzVXoxU9
All I found is that one. it is not all of them.. and shipping cost is awful...

All I am going to say is that you may as well get creative and sub some screws in from other laptops if you can find those with the right thread as paying $35 shipping for a few screws is insane. For $35 you can almost buy two Powerbooks G4s if you were to get lucky, I like iBooks myself but I feel that the prices are inflated and powerbooks are often cheaper or the same price while being faster.

I can buy screws from iBook G3 (white). It is most common then Clamshell. Not sure that fits there though. Maybe some of them

All that matters is the thread and the length of the screws, used to sub in screws when I used to salvage laptops. Sometimes Dell and HP screws will work in macbooks 😈