>not sure I know who this is, though.
Pretty sure it's St. Luke. Although St. Thomas Aquinas was also sometimes called an ox, that was because he was very overweight. The fellow in this painting is slender and the scroll is probably to reference his authorship of a gospel.
from the patriots of Grove, Oklahoma:
"WINGED OX (SAINT LUKE) - Luke the Evangelist, the author of the third gospel account (and the Acts of the Apostles), is symbolized by a winged ox or bull – a figure of sacrifice, service and strength. Luke's account begins with the duties of Zacharias in the temple; it represents Jesus' sacrifice in His Passion and Crucifixion, as well as Christ being High priest. The ox signifies that Christians should be prepared to sacrifice themselves in following Christ."
https://www.cityofgroveok.gov/building/page/ox-winged-saint-luke