Anyone know their antique stoneware makers?

Got a few jugs from a local seller last year before Xmas. Only problem is I forgot to pick them up...until last week. They sent me a message asking if I wanted a refund or to come get them. Whoops! Good, honest, patient lady though! I was buying for one that is for sure 1820-1850. The other two I thought were unmarked when I bought based on one or two photos. Flipped this one over to find a mark on the base. Looks like OS but could be an SO. Couldn’t find anything in a quick google or two. It looks to have some legit age on it rather than being a modern repro but I could be wrong. Pretty sure it’s old though. Has anyone come across this mark before? I could always check with Crocker, a resource someone here alerted me to. However I don’t want to bother them with a jug I imagine wouldn’t be of much interest to them.

 

why not........that's a proud jug !!!!

 

Ha, it is a nice jug. I figured it just very basic. Nice, but nothing special or exciting about it. That is unless SO or OS is more exciting than I know.