Hello.

Hams have them, that parts supply with parts from who knows what.
But, where do you get the parts? everything is is so application specific, right?
Well, for starters, microwave ovens have this wonderful HV supply, DC even!
But, there are other sources.
One apartment complex had four cordless electric lawnmowers that they were junking.
I just had to take a peek.
Inside two are 24 volt Li-Ion packs and the other two have NiMH packs.
The charger on three are the same, just a jumper setting for battery type.
The electric motor in each one is the same.
After a bit of work I was able to remove the motors, each one is fine.
The battery packs are defunct but everything else works.
So, I converted two to corded electric power, not that I do not have enough mowers.
One of the chargers I am using as an aircraft NiCad or lead acid 24 volt charger, switch selectable.
The other three are junk box items at this time.
But, so far everything has been free.