I believe RD350's and RD400's use the same size fork seals, except for Daytona's which have different diameter fork tubes.  Can anyone confirm for me?
			
			
			
				That's correct. 
			
			
			
				Thanks again Joe!
			
			
			
				1973-75 RD350 & 1976-78 RD400     34mm x 46mm x 10.5mm
1979 RD400F & 1984-85 RZ350        35mm x 48mm x 10.5mm