I could make a rig like that for about $200 worth of MDF, maybe even $100. I'd have to use the biggest sheets possible and use 3/4". Would probably take about 4-6 hours I think.
It would also weigh about 100 lbs and be a real nuisance I am sure. This is based on the 4 cu ft subwoofer box I made.
Also, I'd use a craigslist-sourced racing seat or maybe a junkyard bucket seat. The angles would be easy to replicate, just use a jigsaw to cut the two mdf sheets for the sides with a nice S curve. The seat back would also be supported with the MDF, otherwise the seat would tear free of the supports with that kind of angle, since MDF doesn't like sheer force on fasteners (bolts/screws).