Found some 370 volt AC (look like motor starting caps.) in several
sizes at fairly reasonable price, locally.

They would be non-electrolytic and non-polarized. In several values
between 10 and 45 mfd.

May have asked this question before; if so have forgotten the answer!
So forgive me.

But would these caps be OK as filters in the B+ of a conventional DC
power supply. Sixty hertz at 115/230 volt input. (120 hz. ripple).

Ten mfd. sound well within the range for the max. size of a filter on
the cathode output of a typical 5 volt rectifier for example A 45
would be OK after a choke input, in the second or third stage of
filtering.

Am I missing something. These are a physically slightly bigger than
'old' style electrolytics as I remember them. Probably at least two or
three times the volume of modern ones. But cap size especially in home
construction not huge issue?

Comments or contradictions welcomed. TIA Terry