You've got the M35Ai (quad .50 guntruck) and 105 mm artilery piece, M548,
and M88 by AFV Club.
M107 and M109 by Itlaeri, M163 by Italeri and AFV Club, M48A3, M42 Duster, M551 Sheridan, M577, by Tamiya, the aforementioned M113's, M151 by Academy, the new molding is Viet era, the one with the flat fender, M41 by several companies. LVTE.
Also the M5 and M8 Stuarts were used by the Vietnamese, and/or French as were the M24, M8 Greyhound, Whiete Scout car, M3 Half track, `
DML's M274 Mechanical Mule, too.