2 years ago Kinetic announced their LAST unit complete with a price tag. Since then I can only suppose they have either proved it does not work, or it is not cost effective for them to tool up (of hire a sub-contractor to do this) to produce the unit.
I suspect you are right. I was hopeful this unit would be on sale last year but the last news from Kinetic said it was going through the certification stage. Since then there's been no update and I doubt it would take over a year for this process.
I understand that Mode C is now prohibited in Dutch airspace?