[windtrader]

If you choose a later model Newell with ZF suspension parts, Newell may be your only source for these parts.  ZF is very strict with who they allow to sell their parts.  Aftermarket suppliers are very limited within the US.  Others on here have had success using sources outside the US, but shipping costs will be high.

I recently priced a replacement air spring (bag) from Newell that was in stock.  Sit down for this one, $1,139.99.

This is exactly what I wonder about some Newell parts being sole source. As to air bags, one would think a regular Goodyear model could have been made to work and be far more in supply and low price. This topic, if not already covered, would be an excellent one for those dealing with an older (7 - 10 and older) model and increasingly facing replacement of parts like these. Maybe others have found suitable alternative bags.