Not familiar with Van Til 's epistemology. I didn't even know he had one, honestly. So I'm not sure what I am about to propose is a true alternative or not.
When I think of epistemology I think of Jacques Maritain's reflections on Thomas Aquinas in 'Introduction to Philosophy'
An Introduction to Philosophy by Jacques Maritain
That is a rather simple introduction but there is some depth to the philosophy of Thomas Aquinas that may be good for you to explore. Guides to Thomistic philosophy include Pieper, Maritain, McInerny, Chesterton, and Gilson. Nothing like reading Thomas in Latin but not everybody can do that. His Summa Theologica and Summa Contra Gentiles are available in English, but before buying one be sure you are getting a translation that works for you. And read either Pieper's or Chesterton's introductions to Thomas so you can get the hang of reading a medieval philosopher with benefit.
A Select Thomistic Bibliography Topically Arranged