Bontrager do their own tubeless rim strip kit for an equally extortionate price. Not sure if for that wheelset though. JRA were selling some cheap old stock Eclipse rim strips which may fit.. These are what DT now sell as their own brand.
My experience with 355 rims is that mine burped on the first ride out, but re-inflated fine with co2. That was with bonty tubeless ready tyres and the thin yellow tape. I added a layer of gaffer tape to give the tyre less wiggle room, and 300 miles later they've been good as gold.