transportation question Trieste, Italy to Lipica, Slovenia

As you know, I won't be traveling soon, hopefully next spring or the year after. Still waiting for the thief's case to go to trial and meanwhile saving money as the stock market dwindles my IRA. But I can start dreaming and planning, I have a question for all you helpful experience travelers:
My plan is to spend a few days in Rome before the South Italy tour. When that ends in Naples, I plan to take the train to Venice for several days. Because of the thief, I didn't get to see the Lippizan Stud Farm in Lipica. As a day trip I can take the train from Venice to Trieste then a bus to Basovizza. I don't want to rent a car from either Trieste or Basovizza to go to across the border to Lipica. According to Rome2Rio there isn't any public transportation across the border and 5km each way is farther than I can walk. Any suggestions?
Thanks for bearing with me.