Sorry it took me so long to respond, somehow I missed the post when I was looking at new posts, probably the day I was away in court all day. I prefer to use bags but coolers will work fine. The portable aerators are great little devices, walmart, Acadamy, bass pro shops, dicks, cabela's and most bait stores stock them, normally about $10-15 each and run on a single d cell battery, I have a couple I use for longer trips and for fishing, I did go pick up a few extra cheap airstones in case one starts clogging as the little pumps really don't put out much pressure.
Hope all goes well, I know the feeling about losing one in transport. I bought a really rare catfish several years ago, had to stay over one night in a hotel on the way home. Stupid me plugged in a airpump in the hotel room along with a small heater to keep the water as stable as possible. I was tired turned out the lights and went to bed, woke up the next morning and found out the light switch turned off the plug I was using. I was totally sick the next morning when I check on the fish. $400 down the drain. Only one I've ever seen and still to this day would really love to find another one, But I won't try that again!!!!