Naturally if you want speakers, and you use PS3 as a source,
find a used stereo set, almost any will do, as long as it has RCA input.
And use the analog output cable provided with PS3 to get the signal to your amp/speaker set-up.
Used old stereos can be had for very little money.
Or get these amplified PC-speakers, that are available everywhere for 10-20 pounds.
And connect with same analogcable. using RCA-3,5mm adapter from Maplin fir example.
Not the best solution ofcourse, but will give you some sound.And cheap.