I've called stores around my place as suggested, but they only sell super well-known stuffs for every day's customers. The 2 or 3 stores that know brands such as Cayin and so on don't sell them, nor do they propose second hand devices.
I'm really not ready to buy a second hand device without having seen it first. So, I give up this solution.
As for the Cayin CDT-17A, I've taken into account the fact that it sounds dull. It's not the first time I've heard this.
I'd like to know if a tube replacement (new model to be defined), and ONLY this, no additionnal tweaks, could make this dull sound completely vanish and make the Cayin sound really warm, clear and open ? Or is it impossible to achieve just by replacing the original tubes ?
Thanks for your answers.
Cheers