Where can I buy Caroma outlet seals?

the 'replacements' are NOT the CORRECT part. take the old one with you to select the correct new part

Buy a new washer kit / or spare part from bunnings

George these guys are good . I purchased a flush valve from them for a really much older caroma cistern . They will most likely have the part you need .
https://plumbingsales.com.au/

well past used by date
parts will be difficult to get so consider a new cistern

have to know whether you mean water is flowing into the bowl?, or "over-filling" the tank? Could either be a bad flapper(More common), or the "fill-valve" is leaking.

Fixing a leaky toilet is actually rather simple, requiring few tools and just a little time and effort. In looking at Caroma toilets on Google, they appear to be just a standard type of unit, and should present few if any problems for yourself or any handyman of modest skill.

If it is leaking around the base of the toilet - where the toilet sits on the floor, the repair item is a simple wax seal. Here is a tutorial to effect this repair: Replace Toilet Wax Ring. The wax ring is very inexpensive, usually $5 to $10 USD.

If the water is leaking from between the tank (cistern) and the toilet bowl, the job is even easier, as it does not require lifting and moving the entire toilet. A good tutorial for that repair is here: How to Replace Tank to Bowl Gasket . The gaskets, new nuts, bolts and rubber seals come in a kit and also cost only $5 to $10 USD.

I am sorry to hear your Plumber insisted you buy an entire new toilet, but do remember he is in the business of making money!

It is most likely the flush valve gasket. This is the equivalent of a flapper on a normal toilet. You can purchase these seals at plumbingmall.com 750017 Outlet Valve Seal for M5 Flush Valve

Or you may just need to replace the foam seal (between tank and bowl)
, part # 687218 http://alternacorp.com/assets/build/caroma/Caroma%20Price%20List.pdf

The hydraulic cylinder lines are designed to not be removable from the cylinder. There have been people who have done it, me, but it requires redesigning the attachment point. Not for the novice. If you are replacing the part, the new one comes with the lines attached. You must remove the plastic interior in the trunk and disconnect the lines at the pump. If you are only rebuilding the cylinder and reinstalling it, it can be done without removing the lines from the car. You will rebuild it sitting in the passenger seat. you will need the replacement O-rings sold on Ebay.

Bad news, if you are experiencing one cylinder leaking, it is very likely the other two that raise the top will begin leaking very soon. This is because all three cylinders use a rod seal made of the same material that degrades over time. The two remaining cylinders (of five) that raise the trunk almost never go bad because they were originally designed with the O-rings.

Costs:

-New cylinders run $300 to $400 apiece
-About $40 to $60 to have your cylinders rebuilt, apiece
-Around $10 to $20 to buy the O-rings on Ebay

Mark Andrews