A selection of the 28mm modern military vehicles that I've collected (with Copplestone Castings "Future Wars" miniature for scale):
Mitsubishi Type 73 1/2t truck (Kyosho - 1/57)
Revised 1996 "Pajero" model.
Ford M151A2 MUTT (Kyosho - 1/57)
A later model than the version used during the Vietnam War, but the closest in this scale I'm likely to find. The camouflage version is hideous and will need repainted in NATO 3-color camouflage.
General Dynamics M1A1 Abrams tank (Kyosho - 1/60)
Part of the iDriver Pocket Armour series... it can be driven remotely using the bluetooth function of your phone.
Norinco Type 59 (No brand - 1/50)
Larger than most vehicles I use, but because the T-54/55 family of tanks are so small (there was a height maximum for crews) I think it mixes well enough... the length, hull deck height and turret hatches are similar in size to the 1/60 M1A1; the tracks are actually the spares from that model.
Amaraz BTR-80 (No brand - 1/55)
Great size and very cheap.
From L-R: Mitsubishi Type 73 (Kyosho - 1/57), Volkswagen Type 181 (Matchbox - 1/58), Ford M151A1 (Kyosho - 1/57), and Willy's MB (Matchbos - 1/55)