Max, the sad fact of life is that the repair costs are likely to be more than the camera's worth in pure monetary terms BUT the camera's worth far more to you in sentimental terms than £, so is (IMO) worth at least getting a quote for repairs. If the cost is unaffordably high, you may have to reconsider but (again, IMO) it'll be worth spending some cash to keep your memories of your Girlfriend's father alive.
BTW, welcome to the forum and I hope you can get the problem fixed at an affordable price.