Hai,

Would anybody be aware of a manufacturer making 1/48 scale models of complete jet engines or turboprops

I'm not, I'm afraid, but ... when researching my current Hasegawa P-3 build I discovered that someone had once made resin T56s for it. The name eludes me, but the general thought is: have you tried picking an engine type and seeing what Google throws up?

I can only find WWI-WWII engines.

There are a number of resin engines on the market but only piston ones, I have never found e.g. an F-16 engine or somthing like that.

But your suggestion is very good. I'll see what google can do ;-)