74LV123A Maximum Timing Resistor Value

I am currently using a 74LV123A to generate a 29 mS pulse. R = 294K and C = 0.1uF. I recently determined that the pulse is varying too much in width because of the 5% (X7R) tolerance on the capacitor. In order to increase accuracy, I'd like to switch to a 1% capacitor (C0G). The board is already in production and the capacitor must be a SMT 0603 size part. The biggest stock capacitance I can get in C0G in an 0603 package is 0.01uF. To get the same pulse width, I'll need 10X the resistance or almost 3 Meg. Can anyone comment on how practical it will be to use that high a resistance and if it will result in better accuracy?