Bubbleback advise sought

[watchloverdave]

Click here: Rolex Oyster Perpetual Bubbleback 14K Model 3131 (1946) - (eBay item 190155985035 end time Oct-03-07 13:49:33 PDT)

Good morning folks. I found this listing on e-bay and am quite interested in this watch. Does anyone on here know anything about the seller, and what do you think of the watch? It sounds good, but I'm not a bubbleback expert (or any other kind of expert for that matter.)

I love this watch, but don't want to make an expensive mistake. I would prefer to buy through an AD, but I've never seen this model preowned at an AD.

Thanks.