Where can I find this video?

It's here, Chech harem: http://www.tube8.com/hardcore/czech_harem_4/26861621/

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Let me embellish Dutch_Bisexual's link which he missed as being blocked... please combine both lines for the 245 MB download:

www.tube8.com/embed/
hardcore/czech_harem_4/26861621

It looks like D.B. got the correct episode (the fourth one), based on the wooden post and the carton boxes (which may be seen about half-an-hour into the movie):

http://www.czechharem.com/tour/page-3.html

So I am marking our friend's effort as "correct"!

An I.D. for one of the ladies in this episode (for Mona Lee; she is one of the brunettes) was made here:

http://board.freeones.com/showthread.php?776270-Brunette-in-Czech-Harem-4

Oh, look! A more comprehensive I.D. page:

http://board.freeones.com/showthread.php?768632-Czech-Harem-IV-20-Girls-ID&
p=9157109&viewfull=1#post9157109

A rundown of what they came up with (make sure to visit link for explanatory notes):

http://picsee.net/upload/2017-02-25/f7692b8e32d2.jpg

01) Nataly Black
02) Zena Little
03) Tarja King
04)
05) Yvette Yukiko
06)
07) Elle Velvet
08) Lulu Jung
09) Susan Ayn
10) Monalee
11) Emilie
12) Angel Piaff
13) Melisa Black
14) Nella Elmer
15) Sophia Magic
16)
17) Nikola
18) Nina Majestic
19) Besie
20) Cynthia Vellons

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It's here, Chech harem: http://www.tube8.com/hardcore/czech_harem_4/26861621/