Manuscript BNF f.fr. 837 (manuscript C)
The Châtelaine de Vergy appears in 20 different manuscripts. The manuscript chosen as the basis for the Dufournet/Dulac edition is manuscript C (BNF f. fr. 837) - see the editors' discussion of this on pp. 28-29 of your edition. This manuscript is a large collection of 252 texts; the Châtelaine de Vergy appears on folio 6.
Browse a copy of manuscript BNF f. fr. 837 here. If you want to see the list of contents for the manuscript, click on 'Detailed information' in the top right-hand corner.
An ivory casket depicting scenes from the Châtelaine de Vergy (mentioned in the first lecture)
Another example of an ivory casket depicting scenes from the text...
Yet another example of an ivory casket (you get the picture...)