Not sure what you're getting at here.
I assume that the loaded SYSEX data come from running some sort of loader, maybe a midi file containing the SysEx, or a specialised SysEx loaded prog that reads a data file and send the data accordingly. The data that WAS loaded has gone (for whatever reason) and you wish to reload it.
I take it you have 'hex files', are these just the binary data, or do they include the SysEx headers etc as well, as there may be specialised format, or memory addresses to send as well?
Lomg ago, with my Roland LAPC-I card, I uses both methods to load bulk SysEx (instrument patches), I certainly still have variants of different loaders, and also have midi files containing 'ready-to-go' SysEx - if I remember correctly. I was also writing programs to convert one type of data file into another - i.e. some files were totally raw data, and the loaded would add the SysEx headers, checksums, etc, another file might have these xtras built into the data and the whole file could be sent byte-by-byte.
Just a simple matter to work either way, to match the prog to the data, or vice-versa. Then I was working as a programmer back then, doing similar things with various other types of data files.
Anyway, mayne I can help?