Thanks very much ArmorAlley but I don't want to spend so much money for this floppy EMU(I prefer to spend the money to an old Mac
).
I understand that. Do bear in mind that replacement floppy drives are quite heavy and unless you get them locally, the shipping will be expensive. Floppy EMUs will work on any Mac with an internal floppy port and can hold the contents of a micro-SD card.
Original floppy drives are, furthermore, 30 years old and may need some tending loving care (i.e. they need to be fixed).
So many items in the Mac II era are now sold as «untested». Care needs to be taken with them and the original floppies too.
There are available exploded diagrams of the various macs and these list Apple part numbers.
We should all have one of these for each of our macs. The Service Source files have useful info too.
tim.id.au's site is rather good (and not just for some manuals). Here is the Service Source for the IIfx:
http://tim.id.au/laptops/apple/legacy/macintosh_ii.iix.iifx.pdf
The part number for the floppy drive in question for the IIfx is 661-0542.