Anyone know where I can find a dashboard petrol primer pump to shoot petrol into the intake of a K-Jettronic 280 engine?

I need "shade-tree mechanic" advice to keep a 41 year old W460 280GE Bosch K-Jetronic fuel injection system working. Not properly (meaning how Germans do it), but number-8 wire functional - how Kiwis, Aussies and Yanks do it.

The problem is my 41 year old 280GE petrol engine has turned the 99,999 clock multiple times and drinks petrol like a fish as they do. Accordingly, given the cost of petrol (over NZ$3.60 litre), it is driven about 1,000 km (600 miles) a year. And it is not a show vehicle, but just an old and loved member of the family whose age and patina that used to be called shabby is now called chic to the point where it will be left to the children and grandchildren who one day may spend zillions restoring it. For now, it's a matter of keeping it running, on the road and passing semi-annual inspections. For example, when an intermediate short in the ignition meant sometimes turning the key (after replacing the ignition switch) failed to light up the dash and fuel pump (but the starter still worked), I just installed a bypass switch - like the hot wiring they show in the movies. Yes, it means it's easier to steal but theft is not an issue where we live.

I don't have the money to completely rebuild the fuel injection system, or for that matter, buy and master the various speciality vacuum tools required to analyse it. So I would like to try a shade-tree fix. Install a hand primer pump.

The engine starts up immediately when cold. But after driving to a store and shutting the engine down while I shop, pay and load, starting involves about 20 seconds of cranking until pistons start to fire and eventually all six are firing. I replaced the plugs and accumulator that made no difference. If I spray quick start down the air intake, it fires up immediately. But that is a pain every time I stop. And cranking for 20 to 30 seconds is going to wear out expensive starters and flywheels over time.

So, I reckon all I need is a way to build in such a quick start, except rather than use ether, just give a shot of petrol (gasoline) directly above the intake. I'm old enough to remember cars that came with a primer. Essentially a pressure or electric button on the dash, which when pressed, shot a small bit of petrol into the air intake which would then fire the engine until the fuel flow took over.

Yes, I know this is not stock, and yes I know the health and safety members of this forum will not reply with advice, but a warning I will create a fire, so I will assure them I will also install a press-button fire suppression system and never try this at home, inside a building or at a petrol station.

Has anyone done this, or know what to buy the remote primer pump? My first forays into Google Searches come up with more complicated systems intended for diesel cars or boats. All I need is a permanent equivalent to holding a spray can of ether into the air intake.