Owning multiple Cruisers is a good thing (I hope!)
But if you can only own 1, then selling the 55 and getting a decent 80 would be the move. Move any parts you need over from the wreck and sell what's left. An 80 can do everything. And it's good at almost everything. The 55 is a stylish iconic piece of hardware but you are not going very far in it. If you can own 2, then 55/80 combo is an excellent one. I might buy a better 80 at this point, but if you like it, fix what you have. There is no better truck to drive 1000 miles, and then wheel a difficult trail before driving 1000 miles home. You'll find it's a way better adventure vehicle than the FJ55, not because there is anything wrong with an FJ55, but all the weak spots like brakes, steering, suspension, power and comfort are addressed in an 80.
If you can add another to the stable, FJ60/62s are great. Old school vibe, but decent brakes, power steering, airconditioning, and relatively quiet compared to an FJ55. The FJ62 even gets you fuel injection which is a huge plus. Of my 4, the FJ62 is my favorite. Good luck with your decision. My vote, sell both for a lower mile 80.