My brother-in-law (a lovely individual, really, love the guy, but he should not do construction) did it, and he's legendary for his half-assery. As compared to me, full-assery. So anyway, not taking a chance if I don't have to.
Pep Boys around the corner.
6 inches of heater core hose. The according hoise fits in. A squeeze of water pump gasket silicon around before I put it in. 2 hose clamps.
Need 24 hours to test. 1 side seemed "iffy", not going in nicely, but the other side was perfect. So I'll test tomorrow. If the iffy side leaks, I'll do it again with fresh hose (1/2 left). If still fail, then I'll deal with the washer movement.