Hi there
If anyone is looking to scale up I have a few vessels that could be modified.
One is our old copper hot water cylinder. I think it's over 200l. It's not in great condition which is why we replaced it but the right person with the right skills could make something of it as a boilpot. Or I could sell it for scrap value.
Also I have a keg that used to be 50l but someone has chopped it in half and welded in an extended middle section taking it to probably close to 100l. I would imagine this could make a reasonable HLT.
A fair $ price will be attached.
Cheers
Mike