Choices, choices

[lennon33x]

Ok ladies and gents...need some pro input here.

I'm trying to find the best way to allocate funds. Here are my needs:
1) a longer lens. I shoot primes and have a 50, an 85 and a 135. I'm looking at the 200mm f/2.8.
2) a second body. I have the 5D Classic.

So my options are:
1) purchase another 5D
2) purchase an older crop body so that I have a backup
and purchase the 200
3) any other option I'm not aware of?

Philosophy: credit is not an option. I choose to pay with cash.

Any other out of the box suggestions would be great.