You're very fortunate if you still have a final salary scheme. Most of us in industry lost that years ago, unilaterlally withdrawn by employers and replaced by money-purchase schemes, and we're now at the mercy of the gamblers-in-pin-stripes on the stock exchange. :-(

But I certainly don't begrudge anyone a pay-rise, and I think you are entitled to do whatever your conscience permits in order to achieve your end.

Also if, as keeps being said, the main problem is newbie teachers not getting enough to live on and having to bale out in the first two or three years, why not forgo a general pay-rise, and use the money saved there to pay for increased starting-salaries?