Lost ALL my ringtones

So some time ago, I bought some ringtones with iTunes. I had to get a new computer though, and all the ringtones got lost in the switch, including the ones on my iPhone. I'm not sure where I can get them now though.

I would like I note that I have checked in my past purchases, and I didn't see them whatsoever. Years ago, I also bought some ringtones, and they disappeared just like these, but without the computer switch.

Pretty much what I'm getting at is, I bought some ringtones, and I can't find them, even in my purchases. So I'm curious what can be done...