I got a replacement subframe for my HPE VX from Ebay, not that the exisitng one was bad it was just easier. The dreaded Ebay replacement was described as mint although you can guess it wasn't. It was still ok, jnot rotten, but some one had attempted to refurb it, have blasted it and then rather poorly powder coated it. So I had it re-blasted then a local metal works seam welded on thick plates to the lower cross members that run under the engine and gearbox which are commonly used as jacking points. They did a brilliant job also retaining the drain holes to it all looks like standard except it is now a lot stronger. They then arranged for it to be taken back to the powder coaters to be done properly. Total cost £80. Bargain.
I then filled it with Supertrol.