How to calculate the recovery value of sovereign bond restructuring (hair cut)

International banks have issued the concern over one of Asian country USD sovereign bonds may default due to the poor external sustainability.

Accordingly, they have calculate the recovery value of the sovereign bonds based on the present value. Could you please tell me how to calculate the recovery value of the bond (present value)
e:g: par value of the bond is $ 100, Hair cut 10%, they maturity extent for 10 years and prinicpale will be paid equal annual amortization in year 6-10,  Coupon: 3% for year 1-3, 6% for year 4-6, and 7.5% thereafter and exit yield is 8.0%