Keep in mind that VIN numbers are not assigned sequentially at the factory but more a function of when orders are received. I've heard they are making something in the order of about 20 changes a week for parts to improve the quality of vehicles shipping out. I would generally stay away from vehicles that do not have the parking sensors (very useful feature for such a large car in any case) as cars after that feature was introduced generally have more of the early issued ironed out by then. Also if I were you I'd would not consider any 60 kwh cars as for a bit more you can get a 85kwh version with greater range and speed.
If you are looking to buy a used Model S, be very careful as some of the listed prices are absolutely unreasonable and close to what you'd pay for a new Model S. If you buy such a car you will essentially be subsidizing someone else's depreciation so negotiate aggressively if you need to. It's always amusing to see some trying to get for a used P85 what you can essentially buy a new P85D for after the $7,500 rebate.
Don't bother even looking at used Model S priced over $90K because at that point you might as well by an inventory car with the $7500 rebate or a new car with the $7500 rebate.
Here's a 2014 Model S Performance with the Plus Package and only 7K miles that you can buy for $75K:
http://www.cars.com/vehicledetail/detail/622113012/overview/