You can check out the measurements and differences of the rails in a ritz with your wagon r either in your nearest ASS
with the help of any known service engineer/supervisor. If it is possible to fit then get the part no too. then you can buy it from the nearest MGP shop and fix it any local workshops. Other option is if you are the only driver in your vehicle then check out the possiblity to increse the stock seat height by adding a spacer/bolt with bigger nuts where you fix the seat on the platform. For increse the underthigh support you can also increse the foam in the stock seat by the help of any seat cover stiching technician.