Another ship piece? No, we aren't trying to get back to Funkotron here, there just happens to be quite a few space ships in Red Dwarf. This one is a fragment of the Simulant Battle Cruiser, introduced in the series VI episode Gunmen of the Apocalypse, and blown to bits in Rimmerworld. The warship, crewed by evil rogue Simulants through Simulant Country, resembles the shape of a buffollo skull, foreshadowing the western theming of the episode. At some point after the model explosion in 1993, official movie and TV prop collection company "The Movie Reliquary" ascertained and mounted fragments of the ship into certified frame cases. This was the last such piece available from their shop, so if you want one for yourself, you're going to have to forgive the rather confrontational imperative, and...
go for your guns ya scum sucking molluscs!