Hi,
Welcome aboard.
I had a similar problem years ago but didn't know about it until the camera was sent for a repair and they phoned me. Talking to the technician and he said it was easy and cheap to do and I said OK and later on was delighted.
So, putting 2 and 2 together, I guess an experienced technician can do it easily and cheaply but it's not a job to tackle at home. I suggest you work out the price of replacing it if it was damaged and then ask around for the cost of getting it done. Then make a decision.
In your shoes I'd hand it over to the technician, cleaning may be easy but the subsequent collimation is not the sort of thing to do at home. Also, letting experienced people handle a camera means things are noticed and can be put right before it's too late.
Regards, David