If you really need to move a fish it can be done. We've moved big fish all over the US. We also hold the standing record for longest fish transport (Australia to Minnesota - we moved two green saw fish, three guitarfish and a napolean wrasse.
With a Westcoast to Eastcoast move, you'll want about an 8-10 foot round container and a box truck to haul the weight. Run compressed O2 in it and keep the DO above 100%. You'll also want to check water q every hour or two. Make sure to compensate for ammonia and pH (which will drop off). It will have to be a non-stop drive, so you'll want at least three people with you (rule of long runs is TWO awake at all times). Depending on time of year, you'll have to heat (or maybe cool) the water as well. So expect to do some plumbing. I would never put a heater right in a transport box, so you'd have to plumb in an inline heater - which means you'll also be wiring in electric in the truck to run pumps. Deep cycle marine batts work best. I'd take 6 or 8 of them.
May I ask the type of fish? That would have an impact as well.