If the 3 point hitch can lift it and you don't bog down completely when you hit the ground with it, then it's fine. You definitely need front weights or a loader and filled tires for safety purposes. Just don't sink it to the hilt and be easy letting it down and you'll be fine. Keep an eye on your temperature gauge, too.

You could go run around trying to buy another disc, trade, etc, but you've got a tool that works just fine and won't break your tractor as long as you are careful. Only issue I see with an 8 foot disc is transporting it as that takes up an entire lane. Most folks these days complain that discs aren't built HD enough and it's generally true. Sounds like you got one of them old school, built-right discs from yesteryear.

If you are able to break it down in half like you think that may help some.