Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Harlingen, Texas to Venice as you normally would.
For a flight from Harlingen to Venice, you will be flying from Valley Intl. Harlingen Valley Intl (HRL) is just 3.7 mi from the center of the city. Valley Intl is the only Harlingen airport and it handles 0 outbound flights to Venice per day. 0 airlines have flights to Venice from Harlingen Valley Intl on a regular basis.