Marsland do one but I suspect its goin to be cost prohibative.
If one was to make ones own what size tube should one be asking for. I've a vision of one similar to this ....
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but without the need for a tow bar as I've already got one. It may not be pretty but I think it looks better than the alternative.....
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which wouldn't be out of place in a shunting yard. I'm just able to blag my way around purchase of steel plate/sheet but steel tube is a whole new ball game.Fed up of end caps dropping off ( The one not hit by a rover fell off in post incident shock today).
Lee D