1, 3, 5 Ducats, silver with original certificate. Millennium 929-1929

Hello, can someone help me to hestimate the value of this set?

1, 3, 5 Ducats, silver material 900/1000 with original box and certificate (300 sets produced)

Thank a lot

Best Regards

I saw an auction for only one Coin without certificate, the 5 ducats silver, closed at 2400€.

Any idea for the complete set?

thanks