Just circling back to maintain the integrity of information shared on this thread.
I did purchase the long block from Sprinter Depot on the date I posted that I'd made the decision (4/10/19). While they were the cheapest option, their operations have been riddled with delays, and they have been the very definition of uncommunicative. If anyone else is in the position of making a purchase from them, I'd ask a lot of questions about their inventory (e.g. do you have the engine in stock, what condition is it in, is it ready to ship) and shipping procedures (e.g. is your shipping department backlogged, can you guarantee a ship date) before committing to it.
Just to reiterate my circumstances, I broke down in New Mexico; the engine is coming from Texas (i.e., one state away). It took them two full weeks to ship the engine because the block had not yet been rebuilt on the date I purchased it. It hadn't even been pulled from the old van it originated with yet. The machine shop was backed up, so that added another delay. They use an obscure shipping company that only picks up on certain days, which added another 3 days to my wait time. As of this date, I am still waiting to receive the engine, and I still haven't been given a valid tracking number.
It's possible that any remanufactured engine would take this long to arrive, but I have to imagine that other outfits are better at communication and expectation setting. Net net, had I known I'd be paying for a hotel and rental car for an additional two weeks (and counting), it would have changed my calculus.