any b-series header will bolt up, they all use the same flange. however the header you need is dictated by the ecu setup you use. if you indeed have a obd0 b16 (which is the first gen, not the del sol b16, which was the second gen, and would be obd1) then you'll need a obd0 header with two O2 bungs.
if you have an obd1 setup from that del sol, then yes you can buy a header for the del sol. this header will have a single O2 bung near the cat.