I got mine WAY cheaper on eBay and it was genuine.
I'm not saying you can't get "genuine" parts on ebay cheaper and don't have direct experience with this part, but I do think 'genuine' can be very hard to discern.
In my case, I purchased a Canon battery for my Canon camera from Future Shop - it was packaged with Canon logo on the package and the battery was EXACTLY the same as my Canon battery (which came with the camera). In other words, it had the Canon logo on the battery and for all intensive purposes, looked "genuine" and was made to look like it was manufactured by Canon. I bought it as a back-up because I was travelling.
Anyway, within a very short time of using it, my camera started to have communication errors - and I messed around, searched the internet and assumed it was the camera malfunctioning because I had the camera for a couple years. The other problem was the battery looked exactly like my manufacturer battery - so I wasn't even sure which battery I was using as I had them both stored and was using them interchangeably in the camera.
Finally, the camera stopped working, nothing on the internet told me why, so I took it in to Canon and they told me it was a fake or "grey matter" battery. The ONLY difference that I could see between the two (after it was pointed out to me by the canon repair technician) was the fake battery had a more glossy finish and it lacked a tiny stamp on the back which included very detailed manufacturing info. Canon told me that grey matter parts (including cameras themselves) was a huge problem and that have ongoing challenges educating the public. The fact I bought it from Future Shop really was a turn off - it wasn't like I bought it from the trunk of some guy's car.
Having worked in telecommunications, I know the same was true in that industry, so I have to believe Epson is not different.
It cost me $70 for the fake battery, $110 to repair the camera and $130 to buy an actual canon battery from Canon - plus time, money for gas, travel back and forth to Canon and loss of use.
Had my camera been within warranty (1 year) - I would have voided it by using this battery.
All to say, I"m now very much a believer in you get what you pay for . So, unless I knew the source on Ebay and /or had the experience to know EXACTLY what to look for in a replacement part which perhaps this poster has (good on them, they are smarter than me) - I would buy new from B&H or other reputable supplier.
Good luck.
