A500 internal HDD/ Card with Floppy Emulator

Running the A500 with a USB floppy emulator has been a life saver using Octamed. I am trying to run a few synths like FMsynth. Saving the files using the USB method, I can't get my head around. I am thinking maybe using some sort of internal/external compact flash drive / SD card alongside the USB emulator. The ACA 500+ always seems out of stock https://icomp.de/shop-icomp/en/shop/product/ACA500plus.html Does anyone know another solution to get the floppy emulator working with a card or HDD on the A500, would love to hear your thoughts.

Could you do it with a sidecar HD unit ? GVP HD8 kinda thing ?

Thanks mate