After a certain age there are special shops where you have to buy all your clothes. There used to be one in Kentish Town, called Bluston's, but I think it's gone now. You could get those special wool coats that old ladies wear as well as brooches and crocheted hats.
You are, what, mid 40s? You've about another 15 years before you'll actually have to put a suit on to go to the Post office.
If you don't, they'll find you, and kill you.