not really sure about the price.but heres wat i suggest.
dont buy the Honda's original trunk light, it costs 1200rs. instead get 8-10 LEDs installed in the spot.the wiring is already done.this wud cost 400rs, many ppl have got it done.
get any nice exhaust pipe chrome tip from ur local car decoration shop and stick it on,shud cost around 200rs.
the most expensive part will be the central console which has hand rest attached to it.there is no other way but to buy it from honda, see if u can sell ur stock one in the market to get some cash back.other wise its just useless.
and lastly, i dont see how u can put an arm rest on the rear seat without changing the whole seat (i wudnt do that btw)