I have a replacement brake pad information request.

My daughter dropped off her old Raleigh Sport, possibly from 2008 (?).
It is a cute little 24-speed road bike.
I noticed that the brake pads are looking very worn.
The bike has TEKTRO R350 brake callipers and the brake pads are marked P453J.
I suspect that these are the original pads.
I'm sure these pads were common at one point but they are Out Of Stock now.

What are you all using ?
Can anyone suggest a replacement for these pads ?

Binky