Only took a quick look since I'm in the UK and it's way past bedtime but I think #4 in that group can be narrowly dated. With a bit of enhancement to your pic, it looks to be a relatively uncommon backmark for W.H. JONES & CO:
The company was an offshoot from the R & W Robinson business of Attleboro, Massachusetts who used various backmarks between 1812 and the 1840's. I believe the specific backmark for Jones is listed in Albert's button book as "1830s", but I think was only in operation as a separate standalone business from 1835-1840.