HP 48 fans: is this stuff of interest?

[Dave Shaffer]

For other reasons, a friend of mine went looking for her HP 48SX for me, and reported finding "Serial Interface Kit HP 48 to Apple Macintosh Computers" and "HP Solve Equation
Library Application Card for the HP 48 SX." From her report, I got the impression that neither of these had ever been used (and, probably, whatever boxes they were in were never opened).

Are these of interest/value? Thanks for any info.