Could I build a 250 motorcycle with 800 dollars?

I only have 800 dollars and i'm trying to get back on a motorcycle. I have a 82 yamaha maxim 1100 but the cdi went out and apparently that part is the hardest part in the world to find i've looked everywhere i've given up hope. So now i'm just going to try and build a bike I thought it might be the cheapest way to ride again.