Rollin - are you Replacing a Bad Battery (which woulld be thru Ariel Warranty) - or do you need to buy a battery either as a 2nd battery - or as a non-warranty replacement ?
So that you know - your Ariel X52 battery uses the "upgraded" Samsung or LG 21700 battery cells, as compared to the more common 18650 "lesser" cells. Also so that you know - "Reention" is "name" for a mjor China maker of Battery Cases (only) and Reention is NOT a complete battery supplier.
There are "very good China battery manufacturers" that sell to U,S. eBike "brands - and to service their U.S. business - they ship the LG 21700 battery cells to the US from Korea where they are made. Then they ship the battery cases (a whole pletora of makers/styles) to the US from China - and when their good U.S. customers need .
Please note your 2nd battery most-likely have a DIFFERENT charging port syle on the battery. Most likely you have the "ST3" C3-pin usmade charge port on your battery now. Your 2nd battery will have a different port - ST3's are not common - a 2-pin barrel port - or 3-pin XLR charge port eitehr will be fine and you will just need a 2nd charger matching that port - which will be like $30 eBay or Amazon
I say that so you know - these (2) Aliexpress vendors - are two of the "legit China good guys" - with the Correct Product - looks to be about $450 + tax - and will assemble in US and ship from US:
