Damage to a window (the side runners are a bit bent out of shape which now means the window can’t be closed), ball park figure, how much is it going to cost to fix?

So I don't know all the correct terminology. The glass is fine but the window itself opens outwards and upwards from the bottom and on its sides there are metal hinges/struts which have got bent out of shape.

Someone said it's not a big deal and I could fix it myself with a rubber hammer but I'm.worried about breaking it even further and it could come completely off and fall into the street below (and potentially do serious harm to someone) so I'm reluctant to have a go myself.

Was wondering how much I should be expecting to pay to fix this problem? Thanks