Help buying for my bf

I’ve been looking at cuban link chains for my boyfriend for weeeks and they’re not what i’m looking for in terms of price and the style of the piece. the only place that matches what i’m looking for is ebay, many people on reddit suggested ebay but my mom keeps telling me i’ll get scammed. I just want reassurance that we all can agree this guy has good reviews and will most likely give me a good product? never have bought off ebay before so i’m just not sure what i’m supposed to look out for and if this is a fair price for what i’m about to get 😬😬please help