Updated 26 March 2023
This video still is probably from the late 1980s.
1986
This is in New York City, in 1986 (in May, apparently), and the photo is by Ricky Powell.
These photos were shot in New York City, in 1986 (it seems).
This photo is from 1986 and seems to have been taken by Sunny Bak.
Another photo by Ricky Powell, from 1986.
1987
An "ad" for Thrasher gear, from 1987.
This photo seems to be from around 1987 - pre Paul's Boutique.
This is from the cover of Glen E. Friedman's book "Together Forever" (about the 1987 Run-DMC & Beastie Boys tour of the same name).
Unless I'm wrong that is Adam Yauch on the skateboard. And Mike D on the corner. If you can spot Ad Rock let me know. Paul's Boutique came out in 1989. So these photos are from early 1989 or from 1988, I would guess.
And this photo of MCA may be from the same photo shoot.
Also check out this video here: "Beastie Boys HD : MCA On The G-Son Studios Skate Ramp" (probably around 1989).
1991
This photo of MCA with Bryce Kanights (skateboard photographer and former pro skater) looks like it's from 1991.
1992
This photo is from 1992 and seems to have been taken by Ebet Roberts. Check Your Head era. Mike D is wearing Airwalk One's.
This looks like it's also from 1992. Thrasher "ad" (no skateboard visible though).
1992, Japanese TV [?] video footage of MCA ("Beastie Boys HD : Very Rare Japan Footage - 1992")
In Japan, 1992, video still
MCA with Jennifer Finch of L7, in 1992
Also check out this video here: "Beastie Boys on MTV Sports (05-29-1992)".
1994
This is an interview in Thrasher magazine, from around 1994.
This photo is from 1994 (I'm guessing). Ill Communication era. Hurricane and MCA on the sofa. Mike D with a Minor Threat T-shirt. They had a cover version of "Screaming at a wall" on the Sabotage VHS video (which is from 1994).