More than likely if it's a B series VTEC and the ear is broken/cut off, it's an LS distributor. Honestly, if it's working and not throwing any CEL's, I'd leave it alone. If it's OBD0 it'll have two round cream-colored plugs, and if it's OBD1 it'll have two square grey-colored plugs.
If the wires are soldered/spliced/cut there's not a whole lot of certainty, but if it has been spliced and there are OBD0 plugs then it's probably an obd1 distributor with obd0 plugs, and if it's got obd1 plugs it's an obd0 distributor with obd1 plugs (with the reasoning being the only reason you'd splice it was to retrofit a distributor to a harness, and if it was an obd1 distributor there'd be no reason to retrofit obd1 plugs onto it)...
Honestly, I've never heard of anyone cutting and splicing a D-series distributor onto a B-series motor, although I don't doubt that it's possible. Like I said though, if it's working 100% fine and not throwing any codes, I'd leave it alone unless you plan on doing more upgrades to the motor, that would require OBD1.