1997 Mercedes Vario 814d air suspension and conversion

[boronia]

You don't state your location so it is hard to give specific information.

For 1,2, and 3 Google would be your best start.
For 4, perhaps a store that sells tyres in your area.

[Guy_Arab]

you can find out by contacting DAIMLER TRUCKS AGENT NEAR YOU THE MANUAL IS A 1997 MERCEDES VARIO 814 TRUCK WHICH YOUR BUS WAS BUILT ON
IF YOU HAVE NO LUCK MY AGENT MAY HELP IN PERTH
GUY ARAB

[boronia]

I would be very surprised if the truck/van version had air bags, it's even a surprise on buses. Perhaps this was an aftermarket modification or STA request.

I don't know what the poster's qualifications are, but I feel people who ask questions like these and don't know the answers should trust the work to others. It can be dangerous doing such work, and dangerous if it is not done right.

[Guy_Arab]

I checked with Mercedes agent here he tells me contact the DAIMLER TRUCKS IN HUNTINGWOOD IN SYDNEY he tells me also the airbag would be put on by the body builder
give the agent some further info
GUY ARAB

[boronia]

Perhaps contact a company like this (Google for others)

https://airsprings.com.au/heavy-automotive-bus/

and ask if they have an agent in your area who can supply and fit

[boronia]

As an afterthought:
Probably important to consider that these airbags were not part of the original spec for the vehicle, and that it can run quite well on its original springs.

A set up like that would probably only improve the ride characteristics marginally at best, so you should consider whether it is worth the cost of getting them replaced.