Hi, I am looking for a washer for my cistern inlet for a bathroom suite I bought from B&Q (sorry). B&Q have stopped selling these suites and also stopped selling the replacement (diaphragm) washer. The washer is about 27mm (dia) with the centre fitted with a grey plastic insert. The plastic has a small locating pin which goes through a small hole located below the centre. If necessary, I can supply a picture but hope someone can point me in the right direction. THANK YOU.