I believe the 440 takes a 532 3 volt battery. Good luck finding any at a reasonable rate. How long the AAA's last depends, I'm sure, on how often you use it, but when you can buy them for $2 or so for a four pack at any grocery store - who cares? If you can't find a battery (or don't want to pay the price), I can convert your 440 to AAA's for $20 plus return shipping of $10 max (depends on zip code).
The rollers someone referred to are the ones inside the film compartment that break the little chemical pod and thus distribute the chemicals over the film when you pull it out. They should be washed frequently to keep them clean.