Seems like these guys have the aftermarket kit.
https://westcoastsailing.net/hobie-14-dolphin-striker-kit/I’m not terribly impressed with the aftermarket kit, the cable and eyebolt setup stretches/flexes and doesn’t actually add a lot of stiffness to the front crossbar.
On my boat, I used the aftermarket post (which you can purchase separately) but fitted a solid steel rod, similar to the OEM setup, which ended up adding a lot of stiffness.
In the end, if you’re not racing and you’re not using the trapeze, then you may not necessarily need the striker anyway.
sm