You and I can buy a Polini Thor 200 for 2.4k, so you can assume Parajet are paying Polini approx 1.8 - 2k for them. So 3.5k for Cage, Chassis, Arms, Harness, Prop and Tank (including dealers profit margin). I'd hate to see the price of spare parts if you bend it!
TBH. I was suprised when Bailey announced the price of the V5 last year, but people seem to like them (and be buying them) I hope other manufacturers take note and start to produce well designed, reliable, lightweight paramotors at a good pricepoint, as they'd make a killing...