I have never experienced that
crowbar has been a need for the power supplies

It's in large part an economic decision - why protect something if it
doesn't have much value?

In many cases not having a crowbar means not really needing regulation.

Is your desire for regulation mainly to get rid of hum?

I intend to use toroid transformer,
and believe the output voltage
varies somewhat more than for
a standard E-core transformer

I've had good luck buying medium duty (several hundred VA rated) toroid
transformers on E-bay and rewinding them for my own uses. You'll need
something like 1000 VA, and I think these exist but haven't paid much
attention.

It's generally easier for me to add/replace windings to toroid
transformers than to unshellac a E-core transformer and rewind. Some
toroids have shellac type coatings but many of the big ones are just
kinda plastic-wrapped (not exactly heat shrink because heat shrink
doesn't come in toroidal forms!), which makes things really easy.

Tim.