That retainer spring is an assembly aid- - - -once the linkage is installed and adjusted properly, whether or not the spring is there is a moot point. Save the new springs for the next clutch change. I've worked on dozens of throwout forks with the springs missing. There will be no effect on the function unless the linkage gets massively out of adjustment.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!