Back to the original question - Colucessna 400, SR22 Turbo and Turbo-Mooneys all come with built-in oxygen systems as standard equipment.
If you have the sort of money to buy a $600k+ aircraft new and want to fly long legs with more than one passenger I recommend you also look at six-seaters (Saratoga, Bonanza) as they will actually give you decent range with four people on board.
Any aircraft that can take full fuel and fill all seats has tanks that are too small
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In Europe I agree with IO540 that having a Turbo is only worth the expense and the payload penalty if you are a regular high-above-the-weather flyer, which in practice means instrument rated.