Three options:
1. Consider that $200 is the cheapest insurance you will get, to prevent blowing up an engine that works perfectly fine today. If you dump the oil out of that pan over your 1200 mile trip, you will cook the engine and have to spend way way more than $200. So buy a pan if you possibly can in any way!
2. If #1 isn't possible, go with that oversized plug. Get it tight but not tight enough that you will crack the pan. Take an extra plug, and a lot of extra oil (in case you spring a leak.. you can keep filling it up and limp to the nearest service shop) WATCH YOUR OIL GAUGE very very closely. As in, make it a habit to look at the gauge every 2 mins for your entire trip. If you can do this, you'll be fine. At the first sign of anything wrong, stop the car and check the plug immediately.
3. Can't you remove the plug, then put a bolt through the hole with a nut on the inside? Get a bolt that is the same size or slightly larger than the original drain plug, so it fits tightly. Put a washer and nut on the inside of the pan and that will hold the whole thing together. Permanent fix
Buy a topsider and start sucking the oil out. Unless you're keeping this car for more than 5-10 more years, just leave the bolt in and keep sucking the oil out.