I got nice cam sprocket bolts from my local tuner back in the early 80's. Wider heads that can clamp the adjustable sprocket with oval holes. Last visit he saw my bolts and told me that it must be Suzuki and pointed at a set of suzuki cams with sprockets bolted.
Suzuki bolts! I still use my old that has been torqued many times. Next time new.
Below comparison with Honda and Yamaha. Yamaha has a very tight fit inside the hole, head slightly smaller.