You will need the following parts to do a complete rebuild of the swingarm bushings/
2 - 52108-460-300 - BUSH, RR. SWINGARM
1 - 52141-460-000 - COLLAR, RR. SWINGARM CENTER
2 - 52144-460-003 - CAP, DUST SEAL - These can be used parts if they are in good condition with the rubber seal still intact.
Option 1:
Check with your local honda dealer to see if they can do a national dealer stock search.
Option 2:
David Silver Spares show the bushings as special order only. Search by part#
CMSNL show 1 bushing, 2 collars, and 2 dust seal caps available
Option 3:
Otherwise you can try to locate NOS parts on ebay, but be prepared to pay dearly if you find any.