I have these:
1994 Fleer Team Leaders #21 Piazza, Mike
1994 Stadium Club Dugout Dirt #1 Piazza, Mike
1996 Fleer Update #U235 Piazza, Mike
1997 Score #22 Piazza, Mike
1997 Score #501 Piazza, Mike
1998 Bowman International #18 Piazza, Mike
1999 Collector's Choice Starquest Blue #6 Piazza, Mike
1994 Fleer Team Leaders #21 Piazza, Mike
1994 Stadium Club Dugout Dirt #1 Piazza, Mike
1996 Fleer Update #U235 Piazza, Mike
1997 Score #22 Piazza, Mike
1997 Score #501 Piazza, Mike
1998 Bowman International #18 Piazza, Mike
1999 Collector's Choice Starquest Blue #6 Piazza, Mike