They are as rair as rocking horse poo. In late 1986 when Group B rallying was coming to an end the plan was to go with a proposed prototype formula called Group S for 1987 but it was canned. Vauxhall/Opel came up with the Astra 4S which was based on the mk2. It has twin round headlamps a 2.0 turbo engine and four wheel drive.
I have not even seen one in a museum, only in photos. I recall John Welch using one in Rallycross in the late 80's. I have a photo I took in 89 somewhere.