[Question] How original is this Seiko 4205-0155?

So I just bought this puppy a few days ago off eBay for $110 from a top-rated seller. I don't know much about vintage Seiko divers so I just want to know how original is this watch? I'd also like to ask how is the general condition of the watch? It seems like it's in decent condition judging it from the pictures but I'm no expert in the field of vintage Seikos. This is only my second ever vintage Seiko watch purchase so I'm still learning.