Different companies can order and sell the same product under their own name. This is allowed. Therefore you can have the same OEM part, but with different company name labels on them. Often this will affect the price, but the main thing to look out for it that it is a genuine OEM Accessory.
Your local online classifieds: Try searching through a site like Craigslist if there is a board for where you live (or don't mind driving to). Craigslist is full of people who are looking to buy and sell car parts online. There is even a specific board just for car parts listings. With a few simple emails, you might be able to find exactly the part you are looking for, or with someone who knows how to find it.
Pay off your loan. If you still owe money to a lender for your clunker, you'll need to pay off your clunker first. Once your car is paid off, you'll then have the title. No junk yard will take your car unless you possess a clear title.
Sometimes you can save money by using used parts rather than new ones. Some garages will have contracts or partnerships with
junk car pickup where they can get used parts. Ask whether or not this option exists. Not all garages have it, but if your budget is tight you might want to look for one that does. Keep in mind that you may not be able to find a used part for your particular vehicle, even if the garage offers this option, because you will be limited to the stock on hand in the junkyard.
Most parts purchased at a Auto salvage yard average 50% to 75% less than purchasing directly from a main auto dealer. Used auto parts are also many dollars less than Spurious parts (spurious parts - non original parts).
A great source of cheap car parts can be found at a scrap yard. This is where people take their cars when they are nearing the end of their life so that they can be officially taken off the road and so that the owner no longer has to pay road tax. The owners of the scrap yard will strip down each car, keeping parts that still work and crush the rest and sell it. If you need a specific part it can be worth your while phoning round all the scrap yards in your area and finding out if they have what you need. If they do they will be able to sell it to you at a reasonable price.
If you have an older car, the use of the auto salvage yards will give you the opportunity to replace older work out parts with the original manufacturer parts and not generic parts. You do not have to worry about the parts you are buying. Those who make this line of work their profession are very knowledgeable about cars and whether or not the part is workable.