Is there any way to send an output to a script which can then only be sent to one of two addresses? Is the following scenario possible?

I want to send money to a script. This script will require knowing a private key to spend, as usual, but the script is only valid if the money is being sent to one of two addresses. That is, if the transaction has more than one output, it is invalid. If the transaction's output is a standard script to address A or to address B then it is valid. If the transaction output value is any less than x, it is invalid.

In other words, it seems the scripts serve to validate that you can spend the output, but then the output can be spent however the claimant wants. Is there any way to limit how the outputs are spent? All this without requiring a trusted oracle of course.
There's no way for an input script to control the output script, so it can't be encoded into the script itself. However, you can get the same effect with more than one partially-signed transaction. Make a P2SH 2-of-2 multisig address, where you hold one key and the claimant holds the other. Send it some Bitcoin. Then part-sign two transactions from that address, one to A and the other to B. Send the claimant both transactions.

The claimant will only be able to spend exactly the amount you sign for, so if you really want a lower limit you'll need to create more transactions with different outputs.