Yes please - I have just bought a second-hand Carvex with no systainer.
Also which one did you go for? If it’s a Carvex I’ve just bought grub screws to do the wobbly blade fix - let me know if you want one.
For light use where you likely won’t need to replace it that often it makes more sense to just buy it ready-made.
CNC Design (link: Replacement Perforated Festool Type MFT /3-LP Top) will sell you one for £38 at the standard Festool size.
I just had a full 8x4 sheet done at my local friendly...