The film is Big Dick Club by Falcon.
(Not to be confused with Big Dick Society, which is a different film by Jet Set.)
The boy watching at the beginning is Duncan Princo - so far as I know this is his only professional porn performance. While he doesn't join in this scene, his climactic scene involves him getting fucked full-depth by Ralph Woods, which considering that he's only 5'2" is quite an achievement.
The top in this scene is Mike Roberts, as already mentioned.
The bottom in this scene is Roman Heart, one of the most well-known stars of the Falcon stable.
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