In reply to Flinticus:
Its part of the plumbing game. My dad (a builder) has been using the same plumber for the last 30 years, both very good friends.
However, even now the plumber will 'go dark' for a week or so of my dad contacting him,.
It's like the dating game, treat em mean keep em keen.
No point getting mad at your plumber, this behaviour is in his blood. Keep trying him and he'll turn up one day with the right part and finish the job. He's probably just busy juggling 20 clients is all.
Good luck