@bikelover
The ignition is divided into two parts, the primary ignition originates from the silver magnet in the crankcase the CB points are installed on the other side. Proper diognisis will follow this procedure:-
a) inspection of primary and secodry coild winding - in most cases they would need a rewind
b) check the silver magnet - it may have to be re-charged
c) the point needs to be checked, if required replaced and then adjusted -
d) check the ignition coil and replace if needed
there is little room for modifications in the ignition system. Very difficult to adopt one from japanese bike simply because Tiger Cubs typically use wet ignition system whereas Japanese ignitions will fail under such conditions. In Japanese ignition systems, the magnatic field is created inside the magnet this is opposite case with Tiger Cubs.
You would be better off buying a spare motorbike for spare parts - Tiger cubs range between 8,000 to 20,000 depending on the condition - remember this bike has a bottom low rating among other classic bikes