The original mounting hardware on the SVI-738 won't work with any modern(ish) floppy drive, the hole spacing is different. Here's my take on a solution.
The holes are elongated to allow for variation in printers, floppy drives, and the universe. The feet on the prototype in the photo were 2 mm too far apart, I fixed that in the uploaded STL. Please let me know whether I got it right.
The original mounting screws can be used, but with a twist: the short screws from the feet go into the sides of the new floppy drive, and the original longer side screws now go through the feet and mainboard into the case bottom. Or just use any suitable spare M3 screws.
Print two, mirror the other one.
SVI-738-floppyholder.stl | 32.9KB |