Payslips for SET (O)

Hi,
I'm applying for SET (O) next Friday 6th December.
According to the requirement, the payslip must be less than 1 months.
As my company pays salary on 30th of every month, I therefore need November payslip which won't be available till next Monday.
As my UK payroll department is based in India, I would not received the November genuine pay slip in time for my applicaion as I need to request them (my company only do online payslip unless requested).

My Questions are as below:

1. It was stated in the form that I can print my online payslip and get a letter from HR to confirm the payslip is authentic. Has anyone done this before? If yes, is there any sample letter?

2. How many months of previous payslips is required? I'm planning to bring 3 months pay slip. I also have 5 years worth of P60. Will these be sufficient?

Thanks in advance