At these prices and with such a level of uncertainty, I question whether the Toyota platform is worth it at all when an engine gives out.

I have never seen a remanufactured engine, but given the price difference, I would expect nothing but trouble out of one. And after living with my truck and repairing the damage done by previous shade-tree mechanics, I don't think I'd trust a truck that came with a rebuilt engine. Which means, when the engine goes out, that you spend a minimum of around $5000 if you want it to work well again. Meanwhile, old Toyotas can be found for less than $5000, which means that your vehicle is effectively totaled when the engine quits.