Personally I would avoid any NES system with a replacement pin connector unless it was dirt cheap and I wouldn't plan on keeping it. The replacement connectors are pretty much junk. I've used cleaning kits on used systems and got the original connectors to work close to new, I wouldn't bother replacing pins.
As for the Sharp NES TV mentioned above, if I had to replace the connector I would salvage one from a regular NES system so it would still be original. Maybe that's just me.