Solido 1/50 diecast vehicles are identical in size to Tamiya's 1/48 that I have.
UM and ICM also make 1/48 kits (mostly WW2 Soviet lighter vehicles).
If you can find the older Bandai/Fuman/Frog kits that are 1/48. (You have to be careful as some are now charging collectors prices for these …)
SkyBow and AFV also make 1/48 vehicles.
HobbyBoss makes some very nice kits that are inexpensive (again mostly Soviet armour but also KV-1 and KV-2 in German markings and upgrades (ie new cupola, guns, etc – all historical). The T-34s even have full interiors, if you like modelling.
Bronco also makes some Canadian/British armoured cars.
Italeri makes a fuel truck and an Italian armoured car in 1/48.
Airfix makes some British vehicles.
There is also New Millenium Diecast (again, be careful of collector's prices by some sellers).
The Tamiya kits go together very well!