Holiday treasure hunt: printer’s waste

Andrew Honey, Bodleian book and paper conservator, sends this puzzle:

Volume 13 of Conciliorum omnium, generalium et prouincialium collectio regia. Paris, 1644, 37 vols ; (folio), shelfmark fol. BS 12 (t. 13) contains the printed waste shown here.

The boards might have been made to bind the book in Oxford. We know from inventories that Oxford binders were making their own pulp boards – the inventory of Henry Bluett lists “a paire of pastbord moules, a presse to make pastbords” and Roger Barnes has “a trough to make pastboords”. What printed leaves were they using?