the episode where John boy takes grandma to weston

[awesomemixtape10]

there is like a salvation army band. there are 2 suspicious people looking like they are gonna rob the place

[Johnny]

S2E12  The Bequest 
if you mean these two young boys who were watching the Salvation Army Band
they didn't strike me as dodgy, just behaving like young boys. They even put some money
in the pot.  

it may be a good idea to add this new thread to the one in Season 2,  titled The Bequest.