I bought some 10" Celestion drivers from Lean business. They were new (old stock) and ridiculously cheap. Problem is there are no TSPs available and I don't have either equipment or expertise to measure them. They were originally used in the "Substation 10" bandpass cabinet.
I noticed in the "Cubo 12" write up that a) the design was very forgiving and b) that it could work with 10" drivers.
So, it's worth a try but should I scale the cabinet down to suit the 10. If nothing else I think it would be worth scaling the width down a couple if inches, but you tell me???
Cubo 12 is forgiving when it comes to using 10" drivers, you don't have to change the cabinet at all to make it work with 10" drivers. Slimming down the width of the cabinet will smooth the response a bit but nothing drastic, if so I would build it at 35 cm external width. You can also smooth the response by placing the driver with the magnet inside the chamber (magnet not visible).