A few people have been scammed on the site, Only use paypal to pay for items for sale by other members. If they will not use paypal, its likely a scam NEVER SEND E-TRANSFERS OF ANY KIND.
The NC came in 2012 with RK or DID chains. Some RK equipped NC700Xs had chains subject to breaking from improper heat treating of the side plates and Honda recalled certain 2012 bikes to replace the chains free of charge.
The RK link provided shows at least 4 chains of varing cost, quality and features. It also appears there are several locations that RK uses for manufacturing with different pricing. Buying in the aftermarket could make it difficult to determine what level your buying or getting especially on eBay or other discount sights. ????
This is not new....... all chain manufactures have multiple choices in features and quality. Buyers just need to careful is making the comparison and trust the vendor is delivering the product as advertised.