What's your goal? Why do you want 2 turbos? What's the design boost / flow..... start with what you're looking to achieve and work back from there. Once you decide that, then you can look at what common turbos do and try to decide what would fit best for your needs.
For a ballpark, a turbo off a 3-4L diesel should work decently. Not sure what's readily available in that engine size though. Maybe a Mercedes. Most of the gasser turbos I can think of are small (2-2.5L) and they don't make much boost. (Volvo 240/760 is 2.1 or 2.3L and max ~7 psi) so the turbo would probably be way too small even for half a idi.
Probably when all is said and done, a single conventional turbo will get you what you want with much less hassle and cost though.