the slave cylinder is just about as labor intensive as the clutch install. I'm guessing there is no haggling with a dealer for the labor rate. You could try a "mom and pop shop" and hope for a better rate. Since it is out of the warranty period, I personally don't think is a CFM problem. Its a bad deal but it sounds like you are going to have to bite the bullet.
'14 Tuxedo Black ST3
'13 Ingot Silver Escape Titanium AWD
'04 CD Silver SVT, #877, 1 of 135 May 2011 ROTM, FF11: Best Display, Best of Show; AFN12: Best SVT, Best Audio, Finest Five, Carlisle Nifty Fifty