Sorry, but this information is lacking. ALL vehicles that are driven on the roads for any length of time are prone to rust, especially those that have seen salt/calcium chloride. It is not the fault of the car.
For the filter - if you can't get it off with tools, then you may end up cutting it off. I've been told there is a kit for the replacement for when you have to cut the lines. I don't know what the system pressure is, but I would think rubber line would be fine as long as you have the proper fittings.