With Shanty Town, I would even get more than 2 Jacks eventually. Is not really an engine with all the Silver, but it will get you to Provinces and leave Feodum worthing a good number, possibly more than Duchies, which is a nice turn-to when PPR comes. Taking Feodum to 6 VP to fight Provinces seems hard, but 4 VP (12 Silvers) should be easily doable. I woud not buy Silver until the end, to pump up Feodum. If the only terminal is Jack, Shanty Town is (almost) always at least a cantrip, thus better than Silver.
I would open Chapel/Jack, then go on to buy ST and trash everything but Silvers, Shanty Towns and Jacks. I don't like trashing Feodum for Silvers early, if that Feodum was a Jack, it seems it would be better because its likely to be played 3 times or more.