Sewage pump issue

I have a sub grade sewage pump in a basin that my basement bathroom drains to. Today the float didn’t work so my shower and toilet backed up.

I removed the floor to expose the pipe and basin, I lifted the pipe that’s connected to the pump inside the basin about an inch and set it back down. As soon as I set it down, whoooosh…it pumped the basin dry.

I’m going to open the basin and inspect it. Should I just replace the pump while I’m in there or no? It’s 6 years old and gets moderate use. A new pump is around $400 CDN