Stevo,
I've had this issue, and replaced both airbags, after "soapy water" test. It's a 10min job and relatively simple, even for a novice.
Best place to get them is Arnotts in the US, about half the price (landed at your door) of anywhere here in OZ.
Although when I got mine, the $ was .96c not .66c
LAND ROVER Air Suspension Parts - Discovery II Series 1998-2004
They're US$283.80 for a pair + about US$55 postage = AUD$516
That's about $3-400 cheaper than anywhere else in OZ
IMHO they're far better made and better material than OEM or Airbag mans too.
My RHS has started to go down again, and this time it's not airbags. Apparently looks like valve body or possibly the thread that goes into compressor...the search continues
I like the SLS, but a coil conversion could be on the cars, they're only a few dollars as well.
Good Luck

