Not that I know of. I have several OWC Thunderblade drives but they are all TB3.
With the speed of TB5 enclosures now, why do you want to RAID them anyhow? I rarely use my Thunderblade drives any more. I tend to use single enclosures - I just find they perform better, and are less hassle then a RAID enclosure. I'll most likely try to sell my RAID drives as they just sit unused now, and I can finally remove the RAID driver and software from my computer (SoftRAID)!