the ps1 controller is called a dualshock controller it gives out less force than the dualshock2 controller which is used for ps2.
i would'nt go for any 3rd party peripherals because of the quality. when i first bought my play station i had a memory card made by mad kazt. it was ok until one day i played tony hawk 2 and it wouldnt load my saved game. i was really annoyed. just get sony hardware because they last a lot longer and are of better quality.