Where can I find hardware for vintage Marshall cab?

[telewacker]

I need caster sockets and some speaker mounting screws for a 1960A cab circa 1977.

I suppose I can use machine screws from a hardware store...anyone know the size off hand?

The cab has holes in the bottom where the caster sockets were before someone took them out and I'd like to at least put some sockets back in even if I don't bother with the casters.

Thanks in advance

[Gries Amps]

Antique Electronic Supply http://tubesandmore.com/

[telewacker]

Thanks!