Uniform impressions for Vietnamese Army or Viet Cong should be focused on the better equipped, trained and regimented  forces period to the time.
N.V.A. were "regular" Army: combat veterans, and had a standard issue uniform.
V.C. were "guerilla" soldiers and also had a standard issue uniform.

Field Gear and Uniforms should look period and authentic to the impression.

Only Green or Tan Ak-47 magazine chest harness.   Cotton Canvas.
(Modern woodland or blackhawk vests or otherwise will not be permitted.)

Canteen should be of the period issue, colors varried. Example seen in pictures. (You should carry at least two.)

Rucksacks and pouches should be of a canvas or cotton material and look somewhat like period issue.

Tan boots. Desert boots are acceptable.

Khaki Tan four or two pocket uniform shirt / jacket.
Khaki uniform pants w/ or w/o cargo pockets.
(Slaty looking, used Khaki B.D.U. sets are acceptable / No Desert Camo.)

Khaki or Green Vietnamese pith helmet. Khaki or green Vietnamese jungle hat.

Black pajamas are preferred, however Black BDU sets are acceptable.

Vietnamese Jungle hats in green or tan. Coolie or straw hats are acceptable, and scarves are also permitted.

Ho Chi Minh sandals are not reccomended. Khaki, brown, or black boots are acceptable.

N.V.A. & Vietcong Gear Photos & Impression pictures