Ventilo is pretty much a Swiss market only company and I don't expect much at all from Stealthmarine in the way of 18HT. They still list it but I seem to remember that its mould are in permanent storage and have been for a while.
The Stealth 18HT moulds may well make a comeback once I can get finance together for my little project. No cash at the moment, but it's still simmering away in the back of John and my minds.