If you are buying multiples (or bent on making your own like Hachi?
) one could always buy extra and fit an intermediate support in the centre of the long run? Likely, at that price, the extra supports would be timber?
If you are fair at metalwork, it should not be difficult to make a jig and weld up your own. The outer box sections would possibly need the inner seams grinding back level. Apart from that a fairly simple job. Once the jig is sorted, it is simply a matter of cutting metal and welding.
I would paint with original Hunter’s Smoothrite - because I have a good amount, still, in several colours. A metal saw of some description (band, donkey or Rage type) would be a definite asset, too. I also have a shear, which can cut 4mm steel sheet without much effort.
All materials have rocketed in price recently, particularly steel, so I’m not surprised of the price advances. Still too expensive, IMO, when they are so easy to make if one is practical with metal.
