Hello and welcome to r2r,hope all is well.
Tool station. Or plumb centre or just general hardware store you can get your plumbing from in england.
Can go basic white /blue/orange/black/red or whatever colour you fancy within reason,so just look for colour you want or can get white and paint with a reef safe epoxy or paint, or go for harder more durable schedule 40,type in online plumbing pipes in size you want and lots options,all depends if any plumbing on show if want fancy colours as some like to match their skimmer Colour or yo match a secondary colour on sump to spruce it up some, but basic white generally cheaper and if not bothered what colour it is behind your closed cabinet for sump then white does the job.
If doing your own plumbing draw out a plan for it and do some basic measurements and how many elbows /tees/fitting you need so can buy all at once rather than realising you run out and going back store ir waiting for another delivery ha ha
Don't forget gate valves if needed ( these are easier to dial in ive been told rather than ball valves) and some unions don't go a miss incase need to add on or change or maintenance etc.
Good luck and lots knowledgeable people on r2r if start a thread and pick their brains for any questions that may arise ^_^
One little tip,when water evaporates out of a saltwater tank,the water evaporates but salt stays in tank so only top off with freshwater ( preferable rodi water) and having an ato ( automatic top off device) is very helpful as tops off for you rather than manually doing it as we may forget and salinity rises as water evaporates.
Having a rodi unit yourself is alot easier than buying saltwater from store as if need in emergency which sods law will say its when lfs closed ,you can make your own and know its the right sg etc.
