I’m also selling my Canon 5D mk2 for around $350 – it’s had the IR filter removed so is good for grabbing all the light you can throw at it, the rear LCD is disconnected on it so you’d need to tether it to something to see the images. (laptop etc.)
A planetery/guide camera might be a good thing to buy and it’s future proofing your journey into astrophotography (if you choose!)