You could try making your own.
Cut some MDF, thick card, corrugated card, what have you to shape and size. Or be lazy and use old CDs.
Twist some paper lengths or cut thick card strips and tape into hoops. Lay hoop on base and tape or glue down.
Use plaster or wood filler, so on, to create the broken, cracked, surface Creater edge and bottom. Or cut sand paper or card to do it and glue them down.
Apply some glue and sand where needed.
Paint, play, so on.
They are basically free, numerous and each is different. You could also add bits from kits to them, bodies, weapons, downed aircraft, so on.
keeps a convention promise.
