All you need to go triple with top of the range Campag Record parts, suitable for 9/10spd transmissions.
1) NOS chainset, 53/42/30, 175mm arms, crank bolts included, fitted to bike but never ridden £95
2) Used but excellent/minty condition carbon/titanium long cage rear mech £95
3) Triple-specific braze-on front mech, again used but excellent/minty £35
4) Italian thread BB for triple cranks, minimal wear but drive side flange has crack probably due to over tightening in an unfaced/uneven BB shell, does not affect functionality at all and not obvious when cranks fitted. £22 or free if you buy items 1-3.
Hi res pics https://www.dropbox.com/gallery/9092749/1/Record%20Triple%20bits?h=13a42f
If you want a complete group set I have some silver Chorus carbon 9spd Ergos and a cassette I might be persuaded to part with. Note ALL Campag LH Ergos will work with both triple and double chainsets.
Collection SE1/Waterloo or can post anywhere at cost.