Kyran, could you eventually upload your copy of Borland Reflex to Macintoshgarden, please?
Floppy images would be best, but anything else usable should do too.
Some here would give the database app a try for sure.
I would create an image of your app and the needed files with DiskCopy 6 and mount that one with MiniVMac.
A bootable 7.5.3 for MiniVMac is hosted here (5th DL):
http://macintoshgarden.org/apps/macos-753-emulatorsFor opening your database, you might also consider the DOS sibling Borland Reflex 2.0, available at WinWorld PC.
DOS apps can be run in DOSBox or VirtualBox for example, handling files is not really comfortable, but doable.