What is the old Honda spares situation like, Simon ?
IIRC Honda "used" to supply parts for their old bikes, though that may have entailed a long wait. Is that still the case, or are you down to trying Silvers, CMSNL & Ebay etc. for NOS or pattern bits ?
A GT750J & KR1 have rather put me off trying to run an older Japanese bike again - interested to find out if an older Honda is viable as a "useable classic".