A good point of reference for Jim might be Ricky Flynn. He qualified for the 2012 trials with a 1:04 half marathon. He then made his marathon debut at the trials in Houston and came in 12th in 2:13:41. His collegiate PRs were/are very similar to Jim's. The biggest difference obviously is the large chunk of ultrarunning Jim pursued between college and now. And Jim is several years older than Ricky was. I'd say 2:13-2:15 is conceivable for Jim.
https://www.flotrack.org/articles/5024841-mens-results-houston-2012-usa-olympic-marathon-trials