Thanks for the sympathy everyone.
It was a bad day. First the lathe-guy arranges for me to go there, supposedly to pick up the accessories, then surprises me by handing back the deposit then driving off with nothing sensible to say for himself. So, no lathe.
Then my son leaves for overseas again (Panama), this time likely for a long while. He's set himself up as an Amazon seller, doing well, and decided he likes the traveling life. Then while driving him to the airport, while stopped on the M5 due to slow traffic, a semi-trailer rolls gently but irresistibly into the back of our car. Driver distracted, took foot off brake. Minimal damage, but a nuisance.
Oh well. At least in anticipation of the lathe I'd moved a lot of accidentally accumulated junk out of my 'forge shed' to make space for it. So it's now feasible to get that whole stalled building project back on track. And yes, there will be other lathes. Though I rather suspect I'll be lucky to find another with a set of faceplates of all sizes up to huge. That I can afford.
There's no 'deadline' as such. Just a vacuum system project that was stalled for years due to lack of some required (very expensive if bought) parts, that I now have. So now I'm eager to proceed.