Basically any 500 chip controller will work.
I do not know how anxious you are, but the PR has been there since February, so it could be a while.
I normally would not mention to someone new, but from your post you seem to know your way around. I did create a jar with the PR included on my github respository. Releases · apella12/org.openhab.binding.zwave (github.com). The documentation to update a binding was recently improved and is here, if you want to try now or sometime in the future. Bundle Management | openHAB
I have both your devices and have been using this jar (more or less) for about 6 months, so there should not be any problems. When the PR is merged or some other 700 changes are made by the developer, it should be a smooth transition