So... would these be examples of good candidates?

Peugeot Vintage Frame and Fork | eBay

Univega Gran Sprint Frame Set 58cm Classic Lugged Road Cromoly Triple Butted | eBay

Miele Bicycle Road Frame Tange 900 About 58cm | eBay

58cm is ball-parky good for me, not ever actually been fitted it would be close for me at 6'.

Would the Peugeot have French threadings, being French and all?

700c v 27"... I guess it's a horse apiece. I can build either wheel size and it would appear the two can be interchanged with some mods too, so it's a wash.