The X flow is quite a simple thing compared with a modern Ford engine, usually a process of elimination sorts the problem out. Changing the points HT leads, coil, ballast resistor and LT lead wouldn't cost a lot and if they haven't been changed for years may be worth doing anyway. Mine always used to churn over a few times if it had been left standing a couple of weeks before it started and as others have said this was due to getting the fuel through the system to the carb. Is the cold start (choke) working as it should? My old Rangy would not start if left for a couple of weeks unless I used Easy Start due to a problem with the cold start mechanism in the carb.
