Here's a thread on what I did when I way overshot my OG on an old ale and it stalled (or perhaps hit a ABV where the yeast crapped out).
I brewed another, weaker batch, split it between two carboys and blended in the stronger beer. Fermentation took off and it fermented down to a reasonable FG and was still around 10%.
The end result was 8 gallons of awesome beer. I had friends dropping by until the kegs ran out.
I don't recall what yeast I used on the original batch (likely Windsor or Nottingham) but my recent batch I did 5 and 5 with Nottingham and London ESB. I've found that if you treat them right, these yeasts can take a big beer down to a low FG and ABV at +/- 10%.
If you don't want to blend, I'd say rouse the yeast and warm up the fermenter. And/or get a starter going and pitch some fresh yeast. IME you'll need a big pitch for this to work, and patience.