1993 Other Suzuki Models Noise when internal heater fan turn

I have a 1993 Suzuki Sidekick JX. I've never had problems with the fan with the heater/AC before but today when I turned it on (heater) there was a loud, continuous rattling/vibrating noise that kind of reminded me of the sound an outboard motor makes. Maybe like if you stuck a pencil in a running fan. It didn't sound like anything was bouncing around in there as if something had gotten stuck in there. I initially thought maybe a piece of ice got down in there because we had a good bit of freezing rain a couple days ago, but I would think if a piece of ice was in there it would eventually break and I'd hear pieces bouncing around in there. If I turn the fan on a higher speed it gets much louder, like a continuous jackhammer sound. It puts out heat as normal but with the noise I'm afraid to run it. From a little research I'm thinking it could be the blower motor? If this is the case can you give me a general price range of what I could expect to have this repaired? Could it be something a non-mechanical person could fix? Thank you for your time and consideration.