Hi,
This has been getting worse recently. The toilet doesn't seem to have a stop-valve or if it has it is inaccessible ( i can just see a screw using a mirror) so i will have to turn off main tap and i'm worried that if I mess up/need a part we will be without water.

Questions:-
a) It may just need cleaning but it seems to be a sealed unit
b) How does it undo from inside the cistern?
c) Will any decent Plumber supplies carry Sanindusa?
d) should I get a plumber
Photo attached

How can I check if I need the:-

Sanindusa Float Valve 300mm Bottom Entry
or
Sanindusa Float Valve 340mm Bottom Entry

http://www.cisternfittings.co.uk/sanindusa-72-c.asp product photos

Thanks

It would say it's just as easy to swap it out, however you will need to terminate the water supply at the stop cock if you don't have an isolating valve. Disconnect water supply, and you will need to remove the old valve.....if you are happy to do this you are half way there, take the valve to a "proper" plumbers merchants and say to them "have you got one of these or something similar"! Pick up an isolating valve at the same time and fit it now!