Imperial toilet seats have not been manufactured for some time with spare parts being depleted long ago fortunately Imperialtoiletrepair.com.au can assist with a quality replacement

 If you have a Imperial link suite the following description:

Cistern is linked to the pan with a right angle plastic flush pipe 

The seat covers the plastic flush pipe with a "link piece" mounted to the rear of the seat

The cistern is usually secured to the wall  with wingnuts

Then Our X11 seat kit should do the trick 

These seats are a soft close, bright white and made out of thick polypropylene

This kit will include the seat , Instructions and a fixing kit (hinges) and will slide directly into the existing plastic link piece at the back of the seat

Note: While we can supply a replacement, we recommend you use the existing link piece

If you are still not sure what seat kit is required feel free to Email us a few photos the entire toilet paying special attention to the front,  a photo with the seat down and a photo with the seat up 

and we will reply within 24 Hours advising the seat most commonly purchased for your suite.

ALL MEASUREMENTS SHOULD BE COMPARED WITH THE PAN AND NOT THE EXISTING TOILET SEAT 

As original seats are no longer manufactured fitment may differ from the original.