7/64 = windshield washer tubing inner diameter

this was confirmed using a drill bit

but, of course it presumes that the old hose was original

$4 for 5 feet in a bubble pack right near the wiper motor replacements.

it will be a tight fit on the fittings so soaking the end in a coffee mug of boiling water would probably be helpful. as others have noted, the fittings aren't particularly robust but are expensive to replace. so finesse before brute force is the order of the day.

if the hose is still attached, it is better to slit the hose with a razor knife than to try to pull it off.

a barely visible split at the fitting could be the cause of weak washer jet performance since part of the juice goes out the split under pressure. it will also lead to a delay in pumping if the tubing has drained through the split.

nice new shiny flexible tubing, and finally enough to route it properly