A few options:
I'd definitely recommend this pack:
Name: indoch62.zip Size: 3,710,754
Date: 04-21-2009
Downloads: 359
[SIZE=-1]
FS2004 1962 Indochina Scenery. This scenery package contains the major airports for Indochina and Burma as they were circa 1962, based upon material and photographs. The following airports are fully detailed: Rangoon, Burma; Mandalay, Burma; Phnom Penh, Cambodia; Saigon, South Vietnam; Da Nang, South Vietnam; Hanoi, North Vietnam; and Vientiane, Laos. Pakse and Savannakhet, Laos, are done in minor detail with backdated AFCADs. In addition, included are added parking and backdated AFCADS for many minor airports in the region, thus adding parking locations for AI, and removing the irritating strobes, taxi lines, and other features that did not normally exist during the 1950s and 1960s. By Mike Stevens.[/SIZE]
[SIZE=-1]These are a few others you may try:[/SIZE]
Name: sea1srtm.zip Size: 242,057,149
Date: 04-20-2004
Downloads: 9,138
[SIZE=-1]
FS2004 Scenery--Southeast Asia Mesh. Terrain mesh scenery for Thailand, Laos, Vietnam, Malaysia, Singapore as wll as the southern part of Burma and the northern part of Sumatra Territory. Based on SRTM data (3 arc/sec), sampled to LOD9 resolution (76m). While tested under FS2004, this mesh should also run in FS2002. By Werner F. Vogt.[/SIZE]
[SIZE=-1]
Name: vtuu2004.zip Size: 3,033,818
Date: 01-19-2004
Downloads: 2,484 [/SIZE]
[SIZE=-1][SIZE=-1]
FS2004 Scenery--Ubon, Thailand (VTUU). Updated scenery for Ubon Ratchathani airport in Thailand. Ubon was developed during the Vietnam war as an airbase for the USAF. After the war, the Thai Air Force continued to use it as a base, but it also came to be used by commercial airlines to service the northeastern parts of the country. A new, modern terminal has been built and international flights are expected in the future. A landclass and AFCAD2 file are included. By Martin Strong.[/SIZE]
[/SIZE]
[SIZE=-1][SIZE=-1]I recall a few military bases (Da Nang, maybe U Tapao) rendered as per the the military operations of the time - sorry, I can't recall right now where those were.[/SIZE]
I hope those help you get started.
ps: these were on flightsim.com[/SIZE]