It will depend on how your original now fits, if there is still room to tension the chain
then a new 57 might fit and tighten, but when it stretches you will have no way of tensioning
it, unless you remove the link.
It would work better in a larger deeper bar, I have a Carlton bar with a big nose and a 12
tooth sprocket, now that bar would be ok with an extra link as the bar is very close to the drive sprocket
with its correct chain.
Am also told some manufacturers measure their bars differently, some measure from the end of the slot
to the end of the bar, others measure their own pre determined average point of reference which is usually
out an inch of so from the front of the slot, which the manufacturer decided upon based on measuring
the popular saw models from drive sprocket to front on saw casing.
IF the chains are cheap enough, then it may be financially fesable to get a link taken out.
Regards, john