I live in New Zealand and have done since i left the RAF in 1994. My pension is paid into a UK bank account directly from the Paymaster. The original terms of the pension are still extant. Every year I get the same percentage rise as those that still live in the UK. I would presume that those living in Scotland post Independence (if it happens) that are currently receiving a pension will be treated in the same way. However, how any that choose to transfer to the Scottish Armed forces are treated is anybodies guess. Oil will run out soon so where will the countries revenue come from?
More of an issue may be the Old Age pension. As I live in NZ I am entitled to receive the UK pension at 65. However, it is not indexed linked so I am stuck with the starting level for the rest of my days. Unless Scotland is able to get some sort of agreement with the UK government then that may also be the case for you.