Good Deal for 150$?

Just my $.02:

I've used a product called Evapo-Rust on small parts before... pins, hinges, etc... and it works great. It ain't exactly cheap and you'll need several buckets and a big tub to soak that block in though, but I think it's worth it. When you're done, just drain it out and the rust is washed off with the chemical. It's really neat stuff.