1800s engine, electronic ignition and decent mirrors

[chief wigam]

Hi, im in the process of checking over a '63 P1800s that has had very little use over the years with the purpose of getting it reliable and back on the road. When looking at service items, I see that the air filters have a breather hose attached- Am I right in thinking this is a set up from a later car? On checking the side of the engine block, there are cast figures (visible from the passenger side of the engine bay) that also show '1968' amongst others, and from looking at old photos that came with the car, it had an engine out respray years ago, so is it likely that it is a later higher output engine ?
Years ago I had a 1800E that was fitted with electronic ignition, which ran perfectly. Im considering doing the same with this one and notice Brookhouse sells one. Anyone have experience of these?
Lastly, the car came with two unfitted bullet style wing mirrors(at the moment theres only the internal mirror fitted) that look like chrome but are very lightweight plasticky things. Can anyone recommend some either decent quality bullet mirrors or door mirrors as they all look ok on the internet? Any help would be much appreciated . Regards, Phil