Bit more info (pic) would help alot.
but you could try these guys
4mm Air Suspension - Schrader valve to 4mm air suspension refill kits, air compressor bypass kits with a t-piece and couplers for air line repair. Suitable for BMW, Audi, Bentley, Mercedes Benz, VW, Renault, Citroen, GMC, Hyundai and a number of Commercial Vehicles/Vans. This collection contains...
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If you want to pump up the tank think you need 6mm, cant remember the sizes now as it was a while ago (now all a bad dream
) We ran an emergency inflation kit for a short while (e bay have them) till I could get the bits together to fix it.
If you have above (your pic)then you just need a tyre inflation bit that will have the fitting to go into what you show.
Why are you not fixing it properly? You can still run an emergency kit in it should you get caught out.
But TBH when they work well they last a while without problems.
J