Hi Fish,
An alternate idea is make it a soft shackle.
If you have the room in your anchor locker, and the need, you can make it adjustable underdeck , that is if it is not adjustable at the mast.
I have a simple radius plastic deck fitting with one big hole and two small holes. The babystay is soft and has a hardpoint at the top on the mast. It connects to a dyneema lashing with a loop and knuckle on the end, which is fed through the deck plug and anchors via: a 2:1 to a hardpoint on the vertical rear wall of the anchor well.
The following is a pic of the deck fitting and underdeck hardpoint. If I describe it by rope;
- big hole takes the lower babystay shackle (silver) and the rope for the underdeck low friction ring tensioner (blue).
-the lower babystay shackle is the fat silver dyneema one and is a splice. No more than a few feet long. It is connected to the babystay in the pic (you can't see the knuckle though)
-it terminates to the top low friction ring.
-the low friction ring tensioner is the blue dyneema rope, it is fed back through a Karver deck jammer, then through to the starb'd top winch in the cockpit.
-This is the babystay tensioner, the whole 2:1 terminates to a hardpoint in the bottom of the anchor well.
- the little holes take the small silver dyneema loop that acts as the clew attachment.
-this simply ties to the same hardpoint glassed in at the bottom of the anchor well. You set the loop size so it is close enough to the deck, but enough so you can clip your clew onto it.
I haven't got any better photos of the hardpoint itself sorry, it's not ridiculously big and it does takes the babystay tension as well as the halyard tension with no problems.

You may not need the adjustment, but as a minimum I'd keep a 2:1 if you can fit it just to ease pressure off the padeye hardpoint
I'll get photos for you tomorrow if you like as I'm down the boat.
Cheers,
SB
Edit: the babytay shackle lies loose permanently on the deck, you don't push it inside the locker or anything.