UH-1 medic ?

Revell do a UH-1 German SAR version in 1/72 which includes stretchers, howver it is not a particularly good model with regards to fit and chunkyness of the mould. I'm not sure what sort of quality their 1/48 version is, whether it is a new tooling or just a scaled up version of the smaller kit. If you look in the gallery in www.aircraftresourcecenter.com there are a few built up which look prety good. The italeri or ESCI kits are much better in both 1/72 and 1/48 and you can always get hold of the Revell Huey in 1/32 which is an excellent kit. I'm not sure if anyone makes stretchers in 1/35, so you might have to scratch build those. I know the ESCI kit has a winch with it but it goes on the top of the aircraft and I'm  not sure if it was used in this way in Vietnam.

Good luck,

Rich

Something like this:

More pics here.  You can follow the build here, here, and here.

I built this for a customer last year.  It represents a UH-1H MedEvac from the 57th Medical Detachment in Vietnam, "The Original Dustoffs".  It was made from a heavily modified 1/35 Panda UH-1D, actually closer to an H model, sort of. 

Unfortunately, there is no dedicated model of a Vietnam UH-1D/H Dustoff Huey.  Esci did have a UH-1V MedEvac Huey in 1/48, but it was an '80s model.  It is long out of production as well.  The only options out there are to convert one from an existing UH-1D or H model.  

Here are a couple options:

Italeri has a UH-1H in Italian colors in 1/48 and a US Army version in 1/72:

Revell of Germany has a German 1/72 model as well.  It is a later model ('80s) UH-1H though and would need to be backdated.

Hasegawa also has one listed as an UH-1H model in 1/72, but the pic shows both D and H model features, not really sure what it is.

You can get a set of US Army in Vietnam UH-1D/H decals in 4 of the most popular scales (1/32, 1/35, 1/48, & 1/72) from Fireball Modelworks.  It doesn't contain any red crosses or MedEvac specific decals, but most of the common decals could be used.  For crosses, Archer makes a set of WWII ambulance decals in both 1/35 and 1/48, they would probably work.  You could also print you own crosses (as I did) using computer decal paper. 

Good luck.