Message box and vlookup

I have a master workbook with around 500 parts listing different prices in columns D-Q. I then have another workbook where I have 200 of the 500 parts listed (they amount fluctuates) I need a macro that runs from my second workbook, and asks the user to select which part they want updated. Once the part is clicked, the pricing will be updated from the master workbook. I have attached a workbook for an example of what i am trying to do.

I want the message box to ask the user to select which part they want to update and continue to ask that question till the cancel button is selected. AND if it is possible i need an option to update all entries on my second list