A Notepad NC200 lets you put under the disk drive one type 1 PCMCIA card which is a RAM or SRAM card with a button battery to save the ram when outside of the Notepad. The problem is that the NC200 can only hold type 1 PCMCIA cards as type 2 are thicker, too big for the slot. Also these 1 or 2 Mb RAM cards are not much better than the capacity of 1,5 or 2,5 720 Kb disks.
But David Given who is the author of CP/Mish (CP/M for Notepad NC200) has been able to use a type PCMCIA adaptator in which you put a Compact Flash card (16 Mb). CP/Mish is of course able to use such mass storage. However it needs to open the NC200 case to change the PCMCIA slot guide with a new 3D printed part !
You can see his video on Youtube in which you can see the case being opened, so why not also changing the disk drive with an USB Gotek ?