The one they recommend costs $100!!!!! You can get the exact same reservoir from a motorcycle parts store for a fraction of the price, and it's the same size.

"Ex Umbris Venimus"

Yeah, I don't have a manual so I never had to look into it further. If you have the info on the motor cycle resevoir that seems like useful information to the OP's question. Even at an additional $100 that would put the Mopar BBK at $800 which is still below the cost of most other brake upgrade solutions, where replacement pads, calipers and rotors are also more widely available since replacements for these parts which normally wear out can be found at any autoparts store and a multitude of online retailers including aftermarket alternatives.

Bigger booster, and MC filling and providing more pressure in pushing larger calipers is a more complete brake upgrade solution. Sure you can get by with just adding larger rotors, and calipers while re-using the stock booster, MC and notice an improvement in braking but when you understand the entire brake system, you also are able to realize that it is further beneficial to upgrade the additional components to match the use of adding larger calipers and rotors. It's like upgrading your suspension by just adding taller springs and shocks. Those parts will give you the lift you wanted, but adding in the longer control arms, sway bar links and trackbars is what gets you closer to where you really want to be to get the most benefit out of that suspension lift upgrade. It's the same with your braking system.

he sold me! ProGrip added to the list after I install my lift 👍🏼