It depends, and it will be costly if you don't get it done right. My dad has worked for a powdercoating company for as long as I can remember, and trust me, they do not like to do orders in small parts. People are always coming in and asking if they powdercoat rims and stuff like that and they are like "NO" because:
1) It costs too much in wasted time to do a small run of 3-4 parts (unless we are talking like huge parts like whole car bodies, or 55 gallon drums)
2) Alot of companies are set up to powdercoat X amount of stuff at a time, so more than likely, they will just toss your part in with a batch of other stuff, and you may not get the results you wanted and have to wait a while.
3) There really aren't that many powdercoating companies, and even fewer ones that I would trust with a car part that could potentially cause big problems if they mess up.
If you can find one that will powdercoat your stuff for you at a reasonable price, make sure you get some info on them, ask them if they have some other stuff they have done laying around (most shops should have parts sitting around waiting for the set to be finished so they can be packaged up). If you see like smooth and then little volcano looking areas, (which is caused by the way they are held in place when being coated) then you might want to make sure they are a good place. Even good companies have bad runs, but usually it is very limited and they usually trash it. So if they bring you a peice to show their work and it doesn't look good, chances are everything else isn't gonna look good. But really, just look around and try to get references and look at stuff they have done. And if you can't find one that will do small orders, get a bunch of people together and you can do one large order, like if you had 4 friends who all wanted rims or pipes powdercoated, you could do all of them at once and make a large order that companies would be willing to take.
That's about all I can say. But powdercoating can get expensive, and remember, you get what you pay for. Pay cheap and you might get crappy powdercoating.
Oh, and one more thing, if you find a place that will run your pipes alone, and they are like my dads company, it will cost alot, cause they will be losing money by not being able to run alot of stuff at once, and they will make up for it by charging you more. So just shop around before you commit to anything.
