You can't sell access to the Police? Sure you can. The Police just wouldn't be sent to certain people's houses were they to call. That already happens.
National Defense? Why not? Just sit back while some Banana Republic bombs Iqaluit.
There are already private roads in the city (Percy St. just down the block from me). We used to toll Bloor Street.
You can sell access to anything, you just have to come up with a way of administering it if you're really serious about denying others the service. It isn't a matter of being a master logician; we don't entertain these ideas because we're not completely self-interested assholes
That isn't the spirit of the definition. If you were to use that same level of hyperbole than Air is also excludable and rivalrous as you can't breathe the breath I just took, nor what I just exhaled as my lungs have destroyed the air quality by extracting the oxygen and replacing it with carbon dioxide.
This goes back to (almost) exactly what I said:
Roads are a common-pool resource owned by the government and administered (I left that word out) as a public good
(the definition of a common-pool resource:
In economics, a common-pool resource (CPR), alternatively termed a common property resource, is a particular type of good consisting of a natural or human-made resource system, the size or characteristics of which makes it costly, but not impossible, to exclude potential beneficiaries from obtaining benefits from its use. Unlike pure public goods, common pool resources face problems of congestion or overuse, because they are subtractable. A common-pool resource typically consists of a core resource, which defines the stock variable, while providing a limited quantity of extractable fringe units, which defines the flow variable. While the core resource is to be protected or entertained in order to allow for its continuous exploitation, the fringe units can be harvested or consumed.)
Wiki