Oww right in my area indeed.
Straight up I can't see alot of that coin but I had Tealby at the back of my mind when I saw it. However, I can't say with any certainty because there's something I have to say now although it's probably best not to get your hopes up too much.
The Stephen pennies you've seen, and the one I've got, is a generic Watford type (official name is Cross Moline), Watford types are quite distinctive and are the common type, which you coin is not.
However, there are three other substantve types which are rarer, Cross Voided, Profile/Cross & Piles (sound uncomfortable), and Awbridge types. Some of those he faces right, others he faces left, on the profile he faces forward.
However, to make matters much, much worse they are only the Substantive or main types, there are many, many extremely rare regional types, some with erased dies, some with 'PERERIC' rather than 'STEFNIE' in the legend, others with really random legends. I have a picture of a rare type listed in North, which is a coin issued by Henry Earl of Northumbria during Stephen's reign (Henry of Northumbria was the son of King David of Scotland), after the battle of the standard Stephen had handed over Carlisle to the son of the Scots king to buy the Scottish off. That might have kept the Scots off of Stephen's back but it meant the baron who had held Carlisle, one Ranulf of Chester proved to be a complete pain in the backside for the remainder of the reign. Anyhow I digress, this Henry coin is a Cross Crosslets issue.
The problem is there's probably alot of undiscovered types still out there. Not to mention that during Stephen's reign; Stephen, Empress Matilda, Robert of Gloucester, Henry of Northumbria, Eustace Fitzjohn, the Bishop of Durham, David of Scotland, Robert de Stuteville, Henry of Newburgh, Henry of Anjou (better known as Henry II), Brian Fitzcount plus about three other barons were minting coins. And just to show he had a finger in all the pies it would come as no surprise that Henry of Blois was issuing his own coins too.
The safe bet and what I would expect is that your coin is a Tealby issue, but when they get into that kind of condition it could be anything!
Take the best picture you can of it and get in touch with the Fitzwilliam Museum (part of Cambridge University), the curator there could probably put you straight. Trust me they're good, I had what I thought was a defaced die king Stephen penny, that's what the dealer had bought it as and sold it me as. The Fitzwilliam museum soon put me straight and told me it was actually a 12th century German pfennig! Needless to say it went back to the dealer, who sent it back to the dealer he'd bought it off. It had fooled two dealers and me and the dealer i'd bought it from handles alot of Stephen material. In fact he's currently selling a Matilda penny!
So Fitzwilliam s the place you need to ask...
http://www.fitzmuseum.cam.ac.uk/