Acquired a nice(ish) early 1970s Falcon bike recently incorrectly badged as Rory O'Brien, with 1980s Ishiwata replacement forks, 1990s Shimano DT shifters, but interestengly also 1960's Campagnolo gearing. I have few questions for the knowledgeable people here on the Forum

As you can see from the images, jockey wheels on rear mech are cracked and I'm looking for a replacement if at all available? Should I bother to find replacement or if I move these on leave the predicament to a new owner? Is the front matching in terms on the era? Is the seatpost matching too?

Also would anyone know anything about the dropbars marked Ambrosio Coppi Road Pattern, Made in England, and are these also matching the above bits timewise? (will drop pic in when I find it)

Many thanks in advance as usual