i have found you a 25w resistor **broken link removed**
Do not worry that this resisistor is 5w more it will make no difference.
However it is in a different shape and would require slight modifications to the board. you can desolder the one on the board and place two thickish wires in place. you terminate the wires with a crimp terminal and attach it to the resistor.
I cannot see at 1st glance any other sutable resistors
These white ceramic resistors really seem to have vanished from sale these days, I can find very few values still for sale. As far as 20W ones go, I;'ve never seen them for sale in Europe at all, they seem Far Eastern only?.
i have found you a 25w resistor **broken link removed**
Do not worry that this resisistor is 5w more it will make no difference.
However it is in a different shape and would require slight modifications to the board. you can desolder the one on the board and place two thickish wires in place. you terminate the wires with a crimp terminal and attach it to the resistor.
I cannot see at 1st glance any other sutable resistors