It's unavailable through the University of Toronto library system and the Baroda Oriental Institute just confirmed they will not fulfill an order to Toronto.

Wadekar, M. L., ed. The Critical Edition of the Mārkaṇḍeyapurāṇam. 2 vols. Vadodara: Oriental Institute, The Maharaja Sayajirao University of Baroda, 2011. Vol. 1: Adhyāyas 1–75; Vol. 2: Devīmāhātmyam (Adhyāyas 76–88). 

Any direction on how to get my hands on a copy (without flying to Baroda!) would be very much appreciated...

I have seen this being offered by Indian booksellers, e.g., Biblia Impex. By the way, they also list a third volume:

The critical edition of the Markandeyapuranam, Vol.3 (Adhyayas 89-131), critically ed. by M.L. Wadekar, with foreword in English
Year: 2016
Pages etc.: xxiv+691-1218p., appendices, 29cm.
Binding: Hardbound
Place of publication: Vadodara
Publisher: Oriental Institute

Hope it helps,

Peter Wyzlic

-- 
Universität Bonn
Institut für Orient- und Asienwissenschaften
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