Hi
OK I confess, I'm a cheapskate
No, I'm not suggesting to buy 2 Sprague's, but if you just have some broken cams you can replace just those and you can get away it.
It's possible to source those cams from a number of ways, used and new, you can find them in suzukis, ktms, aprilias, ducatis, etc. Usually what changes are the number of cams. The cage of your Sprague usually doesn't have any problems.
For my 600, I've bought a nice used 08 ktm one.
Taffy, hope your secret source has improved his quality, if so, it is a nice option.
Cheers
ZAGA