You can use the MakeHex program to generate a full set of 256 Pronto Hex strings for device code 7D.

Then you can use the IrPanels program to convert that to a CCF file with 256 numbered buttons.

Then you can use the Universal browser to drag from selected numbered buttons.

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Some facts you'll need:

Yamaha uses the NEC1 protocol, so you'll need to use the NEC1.irp file in MakeHex.

MakeHex has no GUI. Double clicking MakeHex.exe gets you nothing. Read the ReadMe file to find out how to use it.

MakeHex produces Pronto Hex in hex (of course) but works with device numbers and function numbers in decimal.

The device number 7D hex is 125 decimal.

The function codes E1 and E2 hex are 225 and 226 decimal.

BTW, I've downloaded and decoded a bunch of CCF files that use Yamaha device code 7D. None of then include commands E1 or E2. So your claim that this one is different from typical Yamaha codes makes sense.