First, please be patient working with support on the issues with the VFD spindle — we should be able to resolve this.
That said, to answer the question you asked, there are various options most of which were looked at in:
FWIW, I do have an alternative spindle on my SO5 Pro (transferred from my SO3 XL) as noted at:
It works well, but I’m still working on the dust collection angle — it’s really amazing how good and flexible/adjustable the Sweepy v2 is, and how elegant the Sweepy Pro is (for all that it is rather overwhelming in terms of its size and presence on a machine) — so would hesitate to recommend it to anyone unless they are willing to either put up with some awkwardness on that front (I switch back and forth between a Sweepy Pro and and Sweepy baseplate adapter as noted in the afore-mentioned thread, and yes, that’s as awkward and annoying as it sounds).
I keep wishing that there would be some other option here, but the existing trim routers and spindles seem workable enough for most folks that working on some alternative doesn’t seem a workable option — I’d love to be wrong.