Google reviews of this boat and you'll find one by Jack Horner of BoatUS:
Who thinks the boat has "no bad habits" in heavy air.
So it would seem you can heel her as much as you want (whether that's a good idea for your crew or not), and she'll recover.
If you're asking how "stiff" she is, or what the heeling limit is mathematically (known as the AVS or angle of vanishing stability), I don't know.
Enjoy this classic boat.