I think he has plenty of tractor for 5 miles of road but to do it and do it without taking all day or night the type of plow he chooses is going to be key. Meaning a run of the mill modified plow truck plow will get pretzeled if he uses the tractor to its full potential. He needs a purpose build snow removal solution built to handle the tractor and what it is capable of doing. Hope that makes sense. There is a youtube vid out there of a Deere over in Europe somewhere with a purpose built plow plowing the roads at full speed, its pretty cool and you can tell the plow is built so it can handle the occasional bump with that much tractor pushing it.
I would agree with the run of the mill part. But I would think that a commercial duty pickup mounted plow could work as long as it wasn't rigged up with down pressure, that will be the real killer, the OP's tractor even well ballasted will only weight about the same as my truck empty.
Something like I posted earlier would still be ideal IMO.