Anyone found this guy I know it's a random encounter but my random encounters seemed to have stopped as well is there like a limit on them

Wrong forum. Ask in hint, cheats and spoiler forum. Ps! There are posts in hcs forum about some rare items and where to find them. The answer is posted in that thread.

Cheers,

Update: Your post have been moved to proper forum. Smiling Larry can be found close to Cambridge Polymer Lab building. Take a walk from Cambridge Police Station (BoS HQ) to CPL. Encounters are random so you have to reload several times before you meet him. Btw, named npc you can hire etc they are not essential, so they can die. Nothing you can do about that.

Cheers,

-Klevs