Isn't a Nippa a Daihatsu L200 underneath? You may have better luck searching for the Daihatsu part.
If they're anything like the Sirion/Storia then you have to buy the arms complete, bushes are not available (in the UK anyway) ... I need two and the arms are about £100 each.
These guys saved me a shed load of money when I bought the arms and that was with Import Tax
The Bush you mentioned isn't a Bush...it's called a 'Cushion'
You'll need 4 of these they all come separate, these also fit L5 chassis
Staddlestones IOW still supply parts 01983871717 give them a bell and ask to speak to Brian in spares.
The cushions are not that expensive either but the Lower Arms definitely will be over £80
As we're in the vicinity of Anti-roll bush rubbers
Hope that helps