Eurotech is one I haven't ever really come across - and from the quick research I have done, that is not a good power supply unit.
I would not use this PSU myself even if it did have a 6+2pin connector, so personally, I definitely wouldn't use it with an additional adaptor.
I know this can seem like a used car sales pitch, but if it doesn't have a 6+2, then it's probably not adequately made to actually power modern GPUs, and if you take the risk, you hugely risk damaging the PSU, which (of that quality) can easily take out your other components too.