Update #1 - I ordered a pair of 2x9 shifters, an Alivio nine-speed for the right side and an Altus M315 two-speed for the left side for that elegant, matching look. The Alivio should be plug and play with the Alivio rear derailleur; it remains to be seen how the Altus will jive with the Acera 3x FD. I've been running an identical modern-day M315 2x with a vintage Shimano 600 FD and A500 53/39 om my Raleigh Flyer for years with little issue.