From the Avotros Klassiek YouTube channel, this HD recording of a complete live performance of the Mass in B Minor on period instruments with the Capella Amsterdam:
Capella Amsterdam also features in Frans Brüggen's version (accompanied by the Orchestra of the 18th century), which garnered a 10/10 review from ClassicsToday:
Brüggen is a long-time master of Baroque performance, and here he shows that mastery at every level, from the perfectly judged tempos to the dynamic choral movements, sensitively shaped arias, rich textural detail, and overall sense of balance between orchestra and chorus, chorus and solo or duetto movements, and orchestra with whatever configuration of vocal forces. The result is a grandly-scaled performance that feels neither long nor labored–and the contributions by all concerned–soloists, choir, and orchestra–are first-rate. Large works such as this, containing so many variables, usually have one or more weak links–an inadequate soloist or two, undernourished orchestral playing, disappointing sound–but no apologies are necessary here. This recording, from a concert performance in Warsaw, Poland in 2009, easily tops my list and reassures me that not only do I not have to accept a flawed performance of this masterpiece (check out the other reviews in our archive), but I–and we–can happily reject any notion of bare-bones Bach in favor of a conception that fully realizes the spiritual power and interpretive possibilities inherent in this much-discussed and debated score.
The orchestra in this video, Il Gardellino, isn't quite as formidable as the OEC, but they're still very fine. And the whole thing is available free to anyone in the world. Internet, I ♥ you.