Oops! Correction. Just checked and the Roud Index does distinguish between the 2. There is only one entry for 'The River Lea' and it is indeed numbered 351, but 'Go to sea no more' has the number 644. I'll adjust my indexes accordingly.

However there is a one-stanza verse of 'The River Lea' titled 'No more pulling on the lea fore brace' at my collection on the BLSA site from the singing of Captain Norman Yates.