Hafler P3000 transformer

I am contemplating the purchase of a 'semi-dead' Hafler P3000 (120V) before making an offer and modding to 230V.
By looking at the schematics, the amps needs +/-18VDC and +/- ??VDC (unmarked higher voltage for the ouputs).
Does anyone know the volt and power specs of the original transformer labeled TT-1531?
Thanks.