Various pumps are available relatively cheap.
However the main problem i have found is the connection to the tyre, fitting or releasing them always seems to cause quite an air pressure loss.
I have a Bosch air pump (other tools with all4 batteries) plus other plug in type in partner's car.
The Bosch came with a screw in type schrader connection. By means of some adapters I have converted this to a clip on type. It is a Laser Tools clip on valve, this works perfectly, other types available just do not seal well due to a hard seal inside or just not sized properly.
The Laser connections are on Amazon -
2 x Laser 5442 Tyre Valve Connector - Clip On/Open End
Sold by: Amazon EU S.a.r.L. £8.43
Photos of the pumps with fittings and purchase details attached