How much State Pension you are awarded is not relevant to the calculation of the Single Scheme Occupational Pension - it is a seperate calculation.
There is an outline in the Scheme Booklet. (
https://singlepensionscheme.gov.ie/wp-content/uploads/2021/01/Standard-Accrual-Booklet-EN.pdf)
Roughly
Use the current
full rate for the State Pension to calculate the Current State Pension Threshold . I make this to be about €49,260 currently. I am assuming you are working full time.
If so, multiply any current gross pensionable salary up to this threshold by 58/10,000 and multiply this amount by your years of service (say 5).This gives you amount
A. Multiply any remaining salary over the threshold by 125/10,000 and again by your years of service (5). This gives amount
B.
Now just add
A + B. This is a rough estimate for your annual pension. This doesn't take account of career averages, so its just a rough estimate. If you are very near retirement it may be an overestimate - or it may be underestimate if you are just starting your 5 years
Your lump sum is 3.75% of your gross pensionable salary multiplied by your years of service. The same caveats apply.