The vintage Honda castings were pretty good, more than worthy of repair. In spite of this, you'll be ahead of the game by simply replacing the broken clutch cover. All-in, which includes finding a seasoned pro to heliarc the break, metalfinishing the repair & repainting, you'll have $75 invested, minimum...plus a couple hours of your time/labor, if you know what you're doing and have the equipment necesary to do the job. As much as I like seeing things fixed & returned to good condition, this is one instance where the OEM vendor is your best friend.