You sound about my dimensions. I think you should be aiming for a 60cm centre to centre seat tube and similar top tube (depending on how stretched out you like to be). You could go higher (I've had up to 64cm in the past without problems, but found that a bit gate-like). I actually ride 58cm these days, with a lot of seat post showing (not good if you want a retro seatpost, but fine with modern ones).
Given the age of my back, I now find I need to have quite a bit of stem showing (for a quill stem; or spacers for threadless) on this size frame, whereas in my younger days I would have the stem slammed right down. Hmm, maybe that's why my back's not great actually...
If you can, get someone to let you have a go on a 60cm as a starting point and see how it feels. If you're aiming for sedate riding, you might want at least that size; if you want something stiffer and more sprightly, and you are looking at old steel like 531, then don't rule out 58.
Hope this helps,
Nick