afang22- as do the waterlines - measure the inner and outer diameter, order silicone tubbing from eBay. Easily done.
It’s unfortunate the safety valve was replaced incorrectly. However - you have to ask yourself why you needed it replaced beforehand, and why you 5 year machine has such issues. Consider using water that is soft and suitable for a coffee machine - rather than relying on in tank water filters.
I also have a 5.5 year old Elizabeth, and, to date, never had to replace any of the valves. It’s very important that limescale does not get built up inside your machine - or eventually it will be a machine replacement.
There are 2 other threads going on the Elizabeth, both somewhat related to hard water.