If you are looking for out of the box ODS tank crewmen in DBDUs/BDUs, the below Dragon set is perfect. You can use almost any ODS-era figure and slap a CVC on it to get ODS tankers in BDUs/DBDUs as well.
It also contains two of the larger M25 mask carriers (green circles).
For USMC ODS tankers in Nomex, there are quite a few options, you just have to think outside the box.
This Paracel set is awesome.
They come as separate figures as well.
You can also use the below IDF sets, with different hats/heads/CVC helmets. The vests are basically US PASGT vests from ODS time frame, just leave off the ammo pouches.
This set can also be used, minus the black guy w/IBAS vest, if you want tankers in Nomex at rest.
