I am pretty sure that Lear is not ETOPS aircraft.
Now, I work for JAR-OPS 1 operator.
We operate twin engine long range business jets with "ETOPS alike Operations" with the approval of local authority.
However, they let us go only for 120 mins anyhow, since none of the business aircraft to my knowledge are ETOPS qualified per say.
For calculating the range, we went to AFM Cruise Control and Flight Planning Manual and in case the fuel or oxygen is not the problem, we can cover around 720 NM in 120 mins.
Hope this helped!