Product review (5 stars): Great washer, great pump.
There are so many of these pumps on Amazon that it is difficult to know which is OEM, authentic, or otherwise. I paid $29 for a pump from A+ Supply, and the description explicitly says that it is an authentic LG part. I can confirm that it is. My pump came in a brown package with a label and bar code for an "LG #XXXXXXX". Don't be put off by the box--it is a "track pack" intended for service professionals rather than consumers. (Consumer packs would have pictures, descriptions, and instructions.) Moreover, the part itself has "PLASET" molded in--that is the Italian manufacturer, and it matches the mold marks on the the old pump and the recirculation pump. It slid in perfectly, and everything lined up with no hitches. Once I got it back together, the washer is as good as new.

If your LG washer displays the OE error, that indicates a pump failure; my original pump failed when the impeller cracked and was rattling around inside the bell housing. If you get that error and it has a loud sound, it is probably a similar issue. Rather than taking the entire machine apart, tip it up and back. I was able to replace the pump by coming up through the open bottom of the machine. It was a bit tight, but very doable.

I got this machine for free because of a bad bearing, and I have ultimately replaced the outer plastic drum halves ($300), solenoid ($9), pump ($29), and spider ($90). It hasn't been cheap to fix, but this machine gets clothes cleaner than any washer or dry cleaner. (Have you noticed that microfiber rags die after a while? They stop absorbing liquids like when they were new. This washer gets microfiber so clean that 5 year old rags absorb just like brand new rags.)

It is easy to simply junk the washer and get a new one. But you are helping yourself and the environment by fixing it.