Most simple system "Irish" flutes were made in London in the 18th and 19th Centuries. As for flute aches and pains the only cure is practice. Eventually you will find a position that suits you. Some people play with the flute resting on their shoulder although that can affect breathing or holding the flute downwards like a chanter on the pipes rather than the classical hold. Don't know if that's helpful. I play both concert flute and simple system flute- the latter for tunes in D G and A and anything else in a more obscure key on the silver concert flute.