You need a cable with 2 RCA females at one end and a 3.5mm stereo male plug at the other. 

Thanks that's really helpful 

What exactly is this old Goodmans turntable anyway? Does it have a built in preamplifier? 

You will probably need a pre-amp as most turntables dont have them.

I have a 70s Pioneer which I have hooked up to my Era 300.

Works well but have to careful of feedback

This is the turntable, it works but is very quite is that why I need a pre-amp, any recommendations?

You’ll need a phono preamp. At a guess the cartridge is probably a moving magnet (MM).

I can’t recommend anything I’m afraid. I got rid of all my vinyl along with a Linn LP12 at least 25 years ago. 

Hi

It’s looks like the phono leads on your turntable are hardwired to it therefore @ratty’s recommendation. If in fact a Pre-amp is required you’ll need the cable type shown here to connect to the Pre-amp input from your turntable. From the Pre-Amp output to your Play 5 you'll need the cable type shown here.

Also as @ratty mentioned the cartridge is most likely MM. If you are not sure there are Preamps that can be configured for either MM or MC (Moving Coil) as shown here.

I just want to say thanks to you guys I am now playing my turntable through my sonos and couldn't be happier!