Fundraiser for yourself - why ever not? It's basically just a normal professional gig, in a sense - you play, they pay, you go home remunerated for your trouble!
Sometimes asking for donations rather than a fixed price gets more money than you would have dared ask for. I'd probably go for that in the circumstances.
Repertoire? Whatever you play well, really. You want to show yourself at your best, after all.
Good luck with it, I hope it goes really well.