Can I circle to a different runway if cleared for an instrument approach without circling minimums?
The only minimums that apply to any approach are those printed on the plate. Doing anything else is being a test pilot. Minimums are charted based on obstacle clearance, descent gradient, distance from the airport, and a variety of other factors.

The appropriate course of action is to either:


land straight in on 31 and attempt to deal with the crosswind. This would be preferred, in my opinion.
go missed and pick up the GPS Y 31 approach and circle to 25. You can't switch approaches once you're cleared. Given the ~1 mile visibility and low ceilings, this would not be ideal.
divert to your alternate if neither of those works. 


Choosing a build-your-own circle with 600' ceilings is reckless - certainly more so than landing with a ~15-20 knot crosswind. There's no guarantee that you'll remain clear of any surface obstacles.